If this is indeed the goal, then isn't there yet. You still need to manually change rural districts, same with special districts. You also need to demolish all buildings inside the zone before the change.
Absolutely. Unless devs will/have confirm(ed) it I can't be certain, but from what i've read they wanted to streamline research/unity into setup similar to Industry, realised that adding 2 more district types is too much clutter, and that's why they went with zones. So the idea was to make specialisation of a planet more streamlined, and I think respecialisation follows.
Not to mention the actual usefulness of such a hot-swap. How often players need to drastically change their unity, research, alloy and CG producing planets? It makes sense when it comes to basic resources. You go synthetic path, you build ring world for food, matter condenser for minerals etc - in these cases you might actually want to quickly swap resource production. It is done once, but can get tedious.
Ehh, so here are a few examples of switching that's quite common.
1. Shortages- as above, sometimes you need to rebuild a fleet, sometimes you need to tech rush, events happen.
2. Excess - as you said, mega structure/idea/tech goes up, and suddenly you don't need all those miners. Or you are finished with ideas, and need to dump unity.
3. Conquest - your enemy planets are rarely well suited for your empires exact needs.
3. Specialist colonies - going from having researchers spread around due to lack of strategics/tech/colonies to grouping them up because issue is solved or relic/ring world is set up.
4. Fortress Spam - for when you really, REALLY need to delay something.
But we don't even have that, rural districts didn't get the same treatment as urban ones
I think currently it's a bit of a mess. In principle it works like this - it takes time to switch specs, this is reasonable, what it shouldn't take is 100 clicks. The current beta system is leagues ahead of standard game when it comes to research/unity but it still has some blind spots and some oddities. The reason I say this is because you used to have to delete 6-10 buildings and rebuild them, and their upgrades, now just 3 + switch zone.
The one missing thing as far as i'm concerned is refinery zone, but they'd have to redisign refinery buildings to make that happen. Also, so far, there far too few buildings to justify three slots for most zones at most times. I honestly like the flat jobs buidings early game to give your planet a bit of a leg up if necessary, but if they are never replaced by anything interesting, then it's better to cut down number of zone building slots so they don't just sit there.
As for implementation - first it's too quick to switch zones, whilst requiring you to manually destroy all buildings and rebuild new ones. The latter can be a safeguard against accidents but it still takes too much clicking and too little in game time compared to switching between mining and energy, for example. However going from mining to urban works the same as going to energy - you need to build the districts (really wish there was easier way to build lots at once).
