Ok, after rereading my last correspondence with Lap, I've sort of begun to see that it's really not going anywhere interesting.
How about we do the provinces similarly to Dominions 3:
Terrain is a token existing in the province description(status bar).
There would be a few types available, some only on specific planet types, but there would be never more than three per province. No terrain token means plains only. Alternatively, always at least one terrain token present.
Each province starts with the same base income, modified by terrain tokens and initially hidden or shown as "income potential" or "income capacity". Province without existing buildings do not generate income.
Building anything creates urbanisation percentage(I'm unwilling to let it go. It's my pet idea) which appears on the provincial status bar and grows until it reaches 100%(meaning all of the income value is collected).
Alternatively, it could grow over 100% for extra building cost.
Graphical representation could be simplified as well, by having a sprite appear for each 10%(or whatever value) of urbanisation on the central part of the province or in the status bar, next to percentage value.
Or we could even ditch it, and simply keep the percentile value.
Bad paint skills are bad, I know. The artistic ones can arrange this better.
Depending on the level of resource variety that makes it into the game, it might be more sensible to put resource production and buildings into a separate window/map layer.
On resources: we could go even further with ripping off the Dominions 3, and instead of stacking resources(micromanagement ahoy!), create a yearly-available resource cap, dependent on provincial industry levels and terrain token modifiers.
Going further this road, metal and energy could be rolled into one "resources" stat, whose planetary total is available in each province with unbroken supply chain.
I'm not sure if the "urbanisation decrases resource production" mechanism is worth keeping, though. Seems a bit like too much of a hassle for too little of an effect?
Special resources could be handled Civilisation style - some provinces would have a randomly generated token representing unique/rare resource type, which would enable some otherwise unavailable units to be produced.
On the province status bar, these would show beneath terrain tokens - representing locally gatherable ones, and in the available resource screen/section, to represent those shipped from other parts of the planet/empire.
Some sort of sharing mechanic between planets would have to be invented, unless simply all unblockaded planets gain access to all of these automatically.
Might require special harvesting building.
The above mechanics have the advantage of making random province and planet generation feasible. One would just need to specify what types of terrain and special resources could be found on which planet type.
Seems a better solution than doing all the planets in the editor, as Davion proposes.
edit: shouldn't this be in Creative Projects anyway?