Data driven Multiblock structures and mob spawning

I feel it would add a massive change in what people could do with datapacks if the multiblock structures functionality could be data driven including:

- Portals
  Nether portals and end portals, if the shape of the multiblock, the entities or triggering action as well as the destination dimension being data driven.

- Beacons/conduits
  Beacons and Conduits having the different requirements for tiering up, what effects are available (or active in the case of the conduit) being data driven

- Golems, ender dragon and wither spawning
  The multiblock that cause the golems to spawn, or the wither skeleton to spawn could be data driven
  The ritual effect for the end dragon respawning being data driven, how the actual ritual itself could be data driven is probably harder to make data driven but could be more powerful if added.

On their own these changes wouldn't allow datapack overhaul mods to work along side vanilla games, you would need additional changes for that - namely the data driven blocks as already suggested here, the ability to add new items, like clones of the beacon, data driven mobs as well as data driven tools/armour and tool levels. However i feel even without those changes having these features be data driven would allow stakeholders to experiment with content additions without needing to edit the base game engine.