I'm not saying they're useless, but for a nether star they're a tiny bit useless in my opinion.
So, my idea is this. I know there are many people out there that hate having to walk long distances back to their house, and in general many people want some form of teleportation in survival. The only problem is that mods like the Tf2 teleporter mod and portal gun mod don't really fit with the game.
So, what one would do is they would build a beacon and place an eye of ender in the place of the diamond/emerald/iron ingot/gold ingot. This would cause the beam to turn a purple-ish shade.
After this when a player throws an enderpearl, instead of flying in the direction he/she threw it, it would be redirected towards the nearest ender beacon. The more layers there are on the beacon the farther away it works.
This wouldn't be too OP because you still need a beacon, eye of ender, and an enderpearl to actually execute the teleportation. Plus, you would need max layers for it to have a far enough effect to be truly useful, and any object in the way would obstruct the enderpearl's path and cause you to get teleported to some random area.
I think this would only be useful in single player, where there is no /sethome or /tp command (unless you have SCP). So I think this would function better as a mod than an actual implementation in Minecraft.
1) What if a player actually wanted to use an enderpearl, but it took them back to the beacon instead of where they wanted to go? There should be some sort of factor that determines whether the ender pearl takes you to the beacon or somewhere else.
Technically, this is already partially possible with the /pt command You could do /pt tppos SilverShadow97 238 65 -379 on an enderpearl and that would work. But, of course, this is only on multiplayer servers with plugins.
Beacons already provide light and buffs, and I feel like this is enough. You have other decoration items in Minecraft that do nothing at all, so I don't think there needs to be a third feature to beacons.
No support - Interesting idea, though, but it'll never happen.