If a region is "purchasable", and immediately producing full outputs on next turn, empires with large pockets will have an advantage over those with poor economy.
Racial perks/negatives would be limited because regions' outputs are independent from population.
Planets will lose their uniqueness because you can just spam mining or industry regions without consideration to the racial population.
Therefore, I'm revisiting my region approach. Instead of "buying" a region, each region will have population capacity. The more people there is in a region, the more the region produces its output. Also, the population in a region will be responsible for developing regional buildings.
So I will implement two exclusive systems: Population Allocation and Output Allocation. Let me explain what those are, then I'll explain why I'm adding two systems.
First, Population Allocation will be a list of sliders for each region (undeveloped regions included), one slider for each race. This is not the same slider system as in MoO 1, rather, this is more like MoO 2's system of population allocation. Except that each region have population limit, and you can define which output each region produces. If all regions have full population, then the sliders will be all the way to the right for each region. However, if the planet's population is not maxed, you can allocate population between each region. Beyond Beyaan default gameplay will use this system.
Output allocation is similar, in that there's a slider for each race in each region. The difference is that this follows MoO 1's system in that all sliders added up equals to 100% allocation for each race. If you were to make a MoO 1 clone, each planet would have 5 regions when settled, (defense, research, industry, environment, and ship), and you can allocate outputs between those 5 regions. The bonus is, if you make a MoO 1 clone, you can have multi-racial output (assigning all Psilons to research, and all Klackons to industry for example)
All sliders can be locked/unlocked for ease of management.
Why two systems? So you can mod the game to use one of the two approaches. If you were to make a MoO 2 mod, you'd want the "Population Allocation" system. If you want MoO 1 mod, you'd use "Output Allocation".
In either system, each region must be first built before it can produce output. You can tweak the colonization process so that it creates one or more regions automatically on colonization (so for MoO 1 mod, it'd create 5 regions, they can't be changed to other regions, and every planet have only 5 regions). Beyond Beyaan will have colony ship land and have no regions developed, and no population, it's basically an outpost. I will implement migration so that people will automatically flow from crowded planets to new planets to ease micromanagement. Again, this can be modded to have no migration if you want.
There will be buildings. I know that I stated earlier that there won't be buildings, but then I realized that part of the fun of 4X space games is development of planets. So there will be region-wide and planet-wide buildings. Region-wide buildings impacts that region, while planet-wide buildings impacts all regions. For example, if you have a building that adds 50% population cap to a region, each region that has that building have its population limit increased. If you have a building that generates a planetary shield, it reduces damage taken for all regions during a planetary bombardment.
And finally, the region's output will be affected by racial bonuses. Let's say that a region produces 1 research point for each 1 population in the region. There are 6 "Scientists" with +0.5 research point bonus, and 2 "Brutes" with -0.5 research point penalty, and 2 Humans with 0 bonus. It would be 1 * (10 pop) + (6 * 0.5) + (2 * -0.5) + (2 * 0) equaling 12 total research points.
If you invade a planet, you have a chance of capturing the developed regions. For each region captured, there will be a chance of acquiring a technology. If a building exists that you don't have technology for, there's a high chance of obtaining that building's technology.
With that out of the way, I'm currently working on overhauling the planets in code. I just wrote a pixel shader that allows me to draw a circle around a planet showing all of its regions in their respective color when viewing a list of planets in the system. For example, if a planet have 6 regions, and 2 are military (red), 2 is industry (blue), 1 is research (yellow), and 1 is mining (brown), then you'll see a circle with 6 sections with those colors. I've drawn a sample picture to illustrate (this is not the artwork for in-game, just concept art):
This will allow you to take a quick look over your planets and see what they're producing at a quick glance. Undeveloped regions will be gray. I will also update the planets list window where you view a list of all planets to use this as well. I hope to have an in-game screenshot soon!