Raids are far too hard right now and not super worthwhile either; the best drops you get out of them are totems of undying if you survive 10 waves of angry illagers. This suggestion consists of two parts: a) making raids easier with a more gradual difficulty slope and an outlandish idea that would make raids worthwhile and also even cooler than they already are.
This is long, so bear with me.
a) There is little to no reasonable way to protect villagers from raids right now. Their AI combined with the large attack range of illager beasts and the infinite patience of pillagers and vindicators means that they won't survive raids unless you constantly redirect all the illagers to players, golems, and trained wolves. This holds even if vindicators cannot break doors down, because villagers not only hug walls and choose bad hiding places (under or over a house, inside a pen), but they also rush from house to house during raids, giving illagers ample time to give chase.
Improving villager AI is a touchy and complex subject, but perhaps making raids less deadly would help, which could also justify how common they are. Currently, raids start very easy with the first two waves having only as many illagers as patrols, but then beasts and witches join, and pillagers and vindicators start gaining enchanted weapons, prior to the wave 10 evoker if you make it that far without dying or the villagers all dying/doors all broken down. There is absolutely no way to defend against vexes and fangs, since they are both fireproof and waterproof.
The revised version of the 10 raid waves is below. Note that outpost captains give 1 bad omen level = 2 waves and patrol captains 2-3 levels = 4 or 6 waves. If captains are killed in a raid, instead of restarting the raid, the number of waves grows. Also, dying currently ends raids, which is actually bad because not all raiders despawn, but the villagers get the idea it's safe to go out and you can guess what happens. Dying should not end raids, even on hardcore multiplayer.
Two disorganized pillagers.
Three disorganized pillagers, one may be an outpost captain.
Four disorganized pillagers, one is an outpost captain.
An illager beast alone, with no saddle, accompanied by a pillager 'ground unit'.
An illager beast being rode by a vindicator.
An illager beast being rode by a vindicator who may be an outpost captain.
A disorganized group of four pillagers and a vindicator.
A proper patrol of three pillagers, a vindicator, and a pillager patrol captain.
A proper patrol of three pillagers, a vindicator, and a vindicator patrol captain.
An illager beast wearing a saddle and accompanied by a vindicator.
An illager beast with a saddle and a pillager riding it, who may be an outpost captain, and a pillager accompanying as foot soldier.
An illager beast with a saddle and a pillager riding it, who is an outpost captain and may have enchants, and a pillager ground unit.
A disorganized larger group of three to four pillagers with possibly one an outpost captain, one bearing enchants, and a vindicator.
A disorganized larger group of five to six pillagers with one an outpost captain, three bearing enchants, and two vindicators.
A disorganized larger group of seven to eight pillagers, half of them bearing enchants, and three or four vindicators, one of whom is an outpost captain.
An illager beast with a pillager, and a pillager and vindicator on foot
An illager beast in iron horse armour with a vindicator with enchants, and a pillager and vindicator on foot
An illager beast in iron horse armour with a vindicator with enchants, and a pillager and vindicator who may also have enchants or be outpost captains
A disorganized group of vindicators and pillagers, some of whom bear enchants, one possibly a captain, and a witch
An illager patrol, with one vindicator patrol captain, four pillagers, and a witch
An illager patrol, with two vindicators, two pillagers, and a pillager patrol captain, and a witch
An illager beast being rode by a vindicator with enchants, accompanied by a witch
An illager beast in gold horse armour with a pillager with enchants, accompanied by a pillager, a vindicator, and a witch
An illager beast in gold horse armour with a pillager with enchants, accompanied by a pillager and vindicator with enchants, and a witch or two
An illusioner, and two pillagers with enchants
An illager patrol with two vindicators and three pillagers, three bearing enchants, a witch, and an illusioner
An illager patrol with two vindicators and three pillagers, four bearing enchants, a witch, and an illusioner
An illager beast being rode by a pillager with enchants, accompanied by an evoker who is a patrol captain
An illager beast in diamond horse armour rode by an evoker patrol captain, accompanied by a pillager, vindicator, witch, and illusioner
An illager beast in diamond horse armour rode by an evoker patrol captain, accompanied by a pillager, vindicator, witch and illusioner with enchants
Changes to illager beast drops: the illager beast has an 8.5% chance before looting of dropping any saddles or horse armour it wears. It also has a 25% chance of dropping one to four leads, three sets of 20% chances of dropping a diamond (so 4% of 2, 0.8% of 3), and is guaranteed to drop 3-5 iron ingots like an iron golem, with the likewise weightings.
Changes to illusioner drops: The illusioner has a 8.5% chance of dropping bow as before, 50% chance of dropping a potion of invisibility, 27% chance of dropping a splash potion of blindness, 75% chance of dropping 1-2 arrows.
If the evoker in Wave 10 is the last enemy to go down in the raid, and the village still has people and intact homes, two bonus/punishment waves spawn as well consisting of one of each villager type zombified and bearing weapons and armour, and an illusioner with an enchanted bow. The weather turns and stays inclement while the raid is active and the chunks these mobs are in are loaded, and the zombie villagers do not despawn nor does the illusioner (or its beast in Wave 12). Curing the zombie villagers removes all weapons and armour without reward, but may help keep the village alive if the raid would otherwise end early in Wave 11. To progress to Wave 12, the illusioner must be killed after all the zombie villagers are cured or killed or despawned, and in Wave 12 there are no requirements. To be more specific:
Wave 11 (all difficulties):
It constantly rains during this wave, no thunder or sun.
An illusioner appears behind 14 zombie villagers, with a mending and flame bow, which has a 30% chance to drop, and this illusioner is a patrol captain, to ensure Wave 12 happens if it is indeed the last raider killed. Other drops are as before.
For the zombies, note that all items that can have curse of vanishing and/or binding will have them, and other enchantments are taken from the average level and rounded down. That is, 1 to 3 level enchantments go to Level 1, and 4 to 5 go to Level 2; unless otherwise specified. The items have a 80% chance of dropping, but things crafted of or with chainmail is reduced to 50%, iron to 40%, gold to 30%, diamond to 20%, and leather to 10%. This includes totems of undying, saddles, elytra, etc.
All zombies are always adults unless stated otherwise.
Farmer: iron hoe
Fletcher: bow (melee only)
Fisher: bow with mending, golden helmet, and leather boots with depth strider
Leatherworker: full leather armour and a saddle
Butcher: iron axe
Mason: iron pickaxe
Toolsmith: iron shovel
Weaponsmith: iron sword
Armourer: iron armour and a shield (not used, just held and melee)
Librarian: enchanted book with riptide
Cartographer: empty map
Cleric: splash potion of weakness and golden chestplate
Nitwit: golden apple and chain leggings, but it is a child
Wave 12 (all difficulties);
It always thunders during this wave, no rain or sun.
An illusioner on an illager beast (that's gotta look weird when it does its duplication spell!) with diamond armour appears in front of 14 zombie villagers, with an infinity and punch bow, which has a 100% chance to drop, and this illusioner is never a patrol captain, to ensure Wave 12 is the last wave. The illusioner also always drops 2 arrows of slowness and 1 normal arrow when killed, although it never shoots them (since it has infinity on its bow), and always drops a potion of invisibility II and a lingering potion of blindness. The beast always drops its armour, 3 diamonds, 5 iron ingots, 4 leads, and its saddle. In other words, both their drops max out.
For the zombies, note that all items that can have curse of vanishing and/or binding will have them, and other enchantments are taken from the average level and rounded up. That is, 1 to 2 level enchantments go to Level 1, 3 to 4 go to Level 2; and 5 goes to 3, unless otherwise specified. The items have a 60% chance of dropping, but things crafted of or with chainmail is reduced to 50%, iron to 40%, gold to 30%, diamond to 20%, and leather to 10%. This includes totems of undying, saddles, elytra, etc.
All zombies are always adults unless stated otherwise.
Farmer: diamond hoe with unbreaking III, mending, and fortune III
Shepherd: iron shovel with silk touch
Fletcher: iron shovel with fortune and mending
Fisher: trident with loyalty, impaling, and channeling, (only melee), a turtle cap with respiration III, and leather boots with frost walker
Leatherworker: full protection leather armour with fire helmet, projectile chestplate, blast leggings, and feather boots, and broken elytra on hand (not worn)
Butcher: diamond axe with sharpness and fire aspect
Mason: iron pickaxe with silk touch, efficiency, and unbreaking
Toolsmith: diamond pickaxe with fortune, mending, and efficiency
Weaponsmith: diamond sword with smite V
Armourer: diamond armour with the chestplate having protection IV, and a totem of undying in hand (not used in combat)
Librarian: full iron armour and a clock
Cartographer: full chainmail armour and a compass
Cleric: a diamond chestplate with thorns, projectile protection IV, and mending, and an iron sword with sharpness
Nitwit: full golden armour all with thorns III, mending, and unbreaking iii, and a golden sword with looting and sweeping edge