This suggestion is a bit lengthy, so please make yourself comfortable. I won't explain super in depth like crafting recipes so that I don't bore you.
The inventor's table is an interactable block meant to be obtained later in the game and has two different uses:
1.) A craftable item and a page of paper inserted into the block will produce a blueprint for the item, which can be used in manufacturer blocks (described later) to automatically craft the item in the blueprint.
2.) It will take certain craftable items from the player and produce a blueprint for a more advanced version in exchange for xp. Ex: A boat inserted into the block will produce a blueprint for a steamboat.
Blueprints can also be given to other players and the crafting schematic will be noted in their crafting handbook.
Before I explain the various technologies that the inventor's table can produce, I would like to suggest some other features that would fit in with the general theme.
The wagon wheel: Crafting component that is used to make various horse drawn wagons and can be improved at the inventor's table.
Wagon types: Chariot (2 wheeled war machine), stagecoach, settler wagon, armored wagon. Wagons can travel up and down one block differences in terrain like a minecart does when it travels along a track slope.
2x2 rail turn and 1x2x1 rail slope: Not entirely a new block, just a more gradual change of direction so that minecarts don't come uncoupled.
Small sail boat: Slightly larger than the regular row boat, and has its own storage on board. Its sail can be dyed and a banner can be attached to the top of the mast as a flag.
Catapult: Siege weapon that can be dragged around by horses. It can launch cobblestone projectiles in an arc.
Cannon: Revolutionary war era cannon, fires farther than a catapult but in less of an arc. Cannon balls and grape shot are the ammunition used (duh) by the cannon, and cannot be fired out of a dispenser.
Oil lakes: Only appear in desert and mesa biomes. Oil can be used as a fuel and is also used to make more advanced items. Oil lakes can be surrounded by tar blocks which can be combined with gravel to make asphalt.
Crossbones: A pirate skeleton variant that spawns only on beaches and islands at night. Its weaponry includes flintlock pistols, blunderbusses, iron swords, and (rarely) hand cannons. All of which mentioned below.
Mounted crossbow: A placeable block in the form of a large cross bow mounted on a stand. It can be used/disused similarly to mounting a horse. Its inventory can hold a single stack of arrows and fires them in a slightly automatic fashion. If it is hit too often by projectiles or damaged in any other way, it will drop itself and any arrows inside.
Firearms: The following will describe firearms and their projectiles before being improved by the inventor's table. They cannot be fired underwater and deployment speed can vary depending on the type. Firearms also reload similarly to a crossbow and reload speed varies as well. Their ammunition consists of iron nuggets, gunpowder, and paper. Firing and hitting things with firearms will decrease their integrity. All firearms have a small amount of melee damage. All firearms also have no knockback (with the exception of the shotgun at close-range). The ammunition used for any firearm cannot be fired out of a dispenser.
Bullet (projectile): The bullet is a projectile that comes out of any firearm. It looks like a small dark gray ball and emits small glowing "spark" particles behind it (like an arrow's critical hit particles). The bullet is also effected by gravity like the arrow and its momentum varies between weapons. Unlike an arrow, it cannot be retrieved after hitting something but it doesn't lose momentum as quickly when it travels through water. Lastly, the bullet travels faster than an arrow but not excessively so.
Flintlock pistol: Very innacurate, and the bullet will "spiral" slightly, but is useful in a pinch.
Black powder rifle: A bit more accurate than the flintlock, but not by much. The bullet will also spiral slightly. The weapon is effective at mid range but damage will decrease when the bullet travels farther. A bayonette can be added to the muzzle, giving the weapon more melee damage.
Blunderbuss: A shotgun-like weapon. It fires a spread of 9 pellets and has a bit of knockback at close range.
Hand cannon: A small hand-held cannon that has a delay fuse when firing. If the player switches to another item while the fuse is lit and the cannon fires, the player will explode. The explosion radius of the cannon's projectile is in between TNT and a wither skull. Recoil will be exerted on the player after firing and will effect the player if they are sitting in a boat.
-->Inventor's Table Upgrades<--:
Trains and their cars are slightly larger than minecarts but not by much. Items can be transferred freely between storage cars and they can be loaded/unloaded via hoppers. Turns in rails have to be made larger so that the trains don't derail. Lastly, trains can move and drift across ice.
Wagon wheel --> Iron wheel (Used to make trains and other useful things.)
Minecart with furnace --> Mine train (A small steam engine that is more controllable by the player. It requires water and fuel to run. Fuel and water usage depends on how fast the train is travelling or when its going up or down a hill. Multiple engines can be connected together to pull heavier loads. The steam engine will also explode if it hits a wall too hard or is damaged in some other way except for removal by hand.)
Minecart --> Passenger car (can seat a maximum of 4 players), livestock transport
Minecart with chest --> Cargo car, coal tender (stores any fuel that would be used by a furnace and automatically transfers fuel to the engine when connected directly behind.)
Minecart with hopper --> Plow (Forcibly removes snow, plants, and mobs that would otherwise slow the train down and collects items.)
Minecart with TNT --> Drilling machine (Removes blocks in front of the train and stops it when it comes to the end of a track. Useful for drilling out tunnels large enough for the train to travel through, but the player has to continually place track in front or else it won't progress forwards.)
Rail --> Hammer (Tool used to edit track direction and couple/uncouple train cars and minecarts.)
Advanced tools are meant to be faster but less durable and precise than their more primitive counterparts. They start off as a "base" from which the tool head can be attached, Ex: a drill head placed on a drill base. They cannot be enchanted, nor can they be repaired. Once the tool head is worn out, you are left with the base which from there you can place another. Tool head material can effect the speed and durability of the tool. Advanced tools can also be used by dispensers for... God knows what.
Shovel (Any) --> Hand drill
Pickaxe (Any) --> Jackhammer
Axe (Any) --> Chainsaw
Hoe (Any) --> Auto tiller
Upgraded firearms require a different ammunition than their less advanced counterparts. They are also more accurate but their damage lacks at close range.
Flintlock pistol --> Revolver
Black powder rifle --> Repeater rifle (A bolt action rifle)
Blunderbuss --> Break action shotgun
Repeater rifle --> Rapid repeater rifle (A rapid fire machine gun-like weapon that decreases in accuracy the longer it is fired. It also has the lowest damage of all the other firearms in exchange for its high rate of fire.)
Crafting table --> Manufacturer block (This block can automatically craft things while the player is away. It requires a blueprint from the inventor's table to craft items, and will only accept the materials needed. It will input items from the top and four sides and will output items from the bottom through a hopper.)
Mine train --> Iron horse (A heavily modified mine trainwith two large wheels at the back that can be used to travel freely across land. It is slightly faster than a horse and seats two players. The iron horse needs to be filled with fuel and water and will explode if it hits a block too hard. Unlike a horse, it cannot jump and strafe side to side in one spot.)
When posting suggestion threads, you are only permitted to include one idea (or closely-related group of ideas) per thread. This thread contains multiple unrelated ideas and is considered a wish list, which is not allowed.