Have you considered the possibility that the problem you think exists in the form of "wealth imbalance" isn't really the problem? They didn't form a socially well-organized group that dominates PC because they were wealthy. They became wealthy because they formed a socially well-organized dominant group.

That they're much more wealthy didn't cause the problem with proto-stomping. Their wealth is just a symptom. The problem with proto-stomping was cause by CCP failing to realize soon enough, that Dust needs high-sec spaces too. Otherwise "elite" players will mostly drive away their newest customers, rather than inspire or teach them how to get out of high-sec.

The main problem is not the money, but the arena we all play in. Nearly each corp has the desire to be on top and nearly all of us have that little voice in us saying i want to conquer it all. It is what drives large corporations. Now there are offcourse also those that just simply want a playground. But from the 60000 planets in EVE of which i'm sure atleast 40000 can be played on, we atm only have what 50 or so planets, each with +- 10 districts. So for those 500 playgrounds, we have thousends of corps that want a piece of it, most actually just want a system of there own, both on the ground as in the sky. But anyways you get the idea, not enough room for all of us. Especially not when there are corps wishing to expand beyond all borders. And the top corps now are only there, because in the end there simply where no other corps large enough in recources to take them on. When we go to legion, i hope CCP realizes that they need to open up a lot more systems to play in, in one go, giving enough time for many thousends more corporations to grow to the same standards as the top corporations now, in turn creating more fun for them aswell.

If you look at EVE, there was once a period many many years ago that there was a corp that controlled it all at one time, i believe it was Goonswarm, but i'm sure that even those that played in Goonswarm knew that once you reach that endgame, the fun of wars are taken out. It is also why there are more larger corporations now, to make sure that there are always large wars, but no endgames. They where given chances to take a piece of the arena, over the many years of history of EVE.
So eventually that will be the same in legion aswell, one corp will not rule all, but more a cluster of different large corporations, giving out space and contracts to the smaller ones. All we need is enough systems to make that a reality and a server that can handle 1000 vs 1000 ground war.

I agree. Its difficult to look at that system and consider it well designed. But its also easier to recognize that in hindsight. Designers are playing a guessing game about what we'll do and sometimes they guess badly. How do they fix it though?

If instead of locking their own districts the blue donut had banded together and helped each other defend their districts would the results have been any different? If none of the proposed solutions would change the dominance of a small group of players, I can see why implementing a solution would be a low priority.

Moon goo isn't a problem in Eve, certainly not to the extent that PC is in Dust. If anything the PC system in needs to become more like moon goo, where districts don't produce isk directly but resources that are sold to other players. Moon goo is also not an isk faucet.

Basically what happens in Eve is the isk faucet mostly pours into the wallets of characters who aren't heavily involved in nullsec warfare (hisec mission runners). What moon goo does is create a conflict driver. The reason you attack an area is because it has resources that you want. When an alliance owns moons, it has to export that goo to hisec to sell to players who are not in the null sovereignty game. Both sides benefit from this transaction. The people not involved in sovereignty buy the goo using isk that was injected into the game, build T2 ships and modules out of it, then sell it and take a profit from the transaction. The isk flows from the bottom up to the moon owners.

In Dust, the isk is given directly to the 1% who then use it to stomp the hell out of all the poors, who don't receive any economic benefit from the PC districts. Completely different.

So what we really need is this:
1) Owners of land don't receive straight up isk - they get resources of some kind that are useful to other players (Eve or Dust), which they sell to get isk
2) Some districts should be more valuable than others. If you control the most valuable areas of space the poorer areas may not be worth the additional effort to try and control. This gives non-dominant player groupings a chance to get into the ownership game without being immediately crushed by the guys at the top of the pile. It also creates conflict within blue doughnuts, those relegated to owning less valuable territory will resent the fact that they're not making as much money which promotes the crumbling of NAPs
3) Some kind of raiding mechanic to suck wealth out of a PC district without having to take ownership of it. This is the big problem with Eve sovereignty - actually taking territory is a giant ballache and it's the only way to cause damage. They refer to the fix to this as "farms and fields" - being able to come in and mess the area up, and leave more wealthy than when you came. The idea is to spread out the conflict so instead of just the monumental ownership conflicts we see once every couple of years, you get small scale and frequent defensive fighting to protect income.