OP’s suggestion is a good idea. Let’s face it, PI was only ever a half-assed cludge to link EVE with Dust and the UI is terribad. The transition to planets being solely a source of P0 (without having to fartass around with ridiculously unintuitive colony setups) and then having all other processing occur off-world (the same as everything else in EVE) would actually bring it more in line with existing EVE mechanics.
As to POCOs and muh tax streamz… Get rid of them. Or re-work them into a new system that doesn’t boil down to entire planets being owned by 1 player.
People citing P0 m3 volumes as an issue have missed an easy and obvious solution: Reduce the m3 size of P0 (and all other PI intermediaries). As it stands the current system is a bit ridiculous in how many m3 of P0 it takes to produce a single p4 product (and where is all that waste m3 going? Currently it magically disappears into /dev/nul. I’d hate to see the wastelands we’re leaving behind on the planets with all these PI factories).
Sure, farming livestock in a space station doesn’t make much sense, but neither does having to manually click on d-scan every 2 seconds, or warping through planets, or bouncing off stations/ships, or the sovereignty system. In fact, pretty much nothing in this game makes sense.
The alternative to this would be for CCP to fully embrace planets (and moons) as part of the EVE universe, with actual gameplay associated with them (and no, the current PI system isn’t gameplay, it’s busy-work), instead of them just being 1 dimensional set pieces serving as a means to an end like every other orbital body in the game. Original PI took us about 2% in this direction.