I'm not really trying to claim a level playing field here. It's more of a case that Leinster are looked at and it's like "how could they not be doing so well?", when in reality they are an exceptionally run organisation maximising efficiency and is the main driver for national success.
I think changing the CC system now is risky. Until all provinces' academies are running at an acceptable standard, any tampering risks losing key internationals. Increasing the number of CCs and reducing wage budgets benefits Munster but likely hurts Ulster, who won't get any, and Connacht, who are due Hansen being offered one at next renewal anyway. A CC quota per province runs the risk of lads going abroad rather than to another province where there's ample examples of resistance.
Leinster are self sustaining insofar as their academy products are enough to be competitive in Europe and URC, Munster are getting there and will be boosted by recent promising 20s graduates, Connacht probably don't have the resources to get there in any case but look to be producing talent at a higher rate than previous, Ulster is a basket case.
On an international level having a dominant team isn't a bad thing, see NZ. I don't think prioritising provincial competitiveness would bear fruit. I think the current system supplemented with incentives to graduate academy players (this doesn't have to be equitable and can somewhat counter Leinster's advantages mentioned above) is the first step. Build from there. Getting Munster to Leinster's level and Ulster and Connacht to Munster's should be the goal, not lowering the level to increase competitiveness.