I feel the risk/reward of building power generators is completely out-of-whack. You take a relatively low investment cost (~100 requisition) to place a power generator, but the reward for having power generators is a massive advantage in tech - especially if your opponent doesn't maintain power generator parity. This system quickly leads to huge resource advantages for the player who owns even 1 or 2 points more - because having that enormous income in power means he can heavily out-produce you in upgrades/vehicles AND still maintain a decent requisition army.
Relic implemented a system of increasing costs to build a generator for each generator already built, but the increase really isn't enough to be that noticed (unless you already have like 5 generators built... but by then you are already doing great).
This system is also why you see a lot of players just immediately build power generators whenever and wherever they can - even if they have no LP or any hope of successfully defending that area - for the simple reason that the (not-so-small) chance of it staying alive and churning out a boost of +50% - 100% more power is such a massive boost in economy.
While the game is certainly playable with this system, I think it promotes shallow strategy (no-brainer decisions are always bad for strategy games - the choice to build power generators is nearly always the correct choice) and also contributes to the snowball factor of being forced of the field. The latter issue is more multi-faceted (for example; most 1v1, and some team game, maps are really small so it makes winning fights and gaining a huge % of map control very easy - further compounded by the fact that the entire economy system in Dawn of War is based off of map control).
- Increase cost of building power generators: The investment should be heavy considering the reward of having the massive power boost. Honestly, it should cost more like 200 requisition to build the first one and increase the cost from there.
- Increase build-time: Making power generators take longer to build will lessen the probability of successfully getting a generator up in an area you cannot defend but merely capped with a worker. On high-level games, it feels like a very frantic and constant battle to continually scout these power generators and kill them so I don't get out-teched instantly.
- Reduce the +power income per generator: This effect would also solve the problem, but would have larger implications on other parts of the game (like late game) as it would make vehicles and upgrades scarcer. Not a bad thing and it might encourage more careful play of vehicles and saving them (addresses some concerns of "spam" and expendable unit feelings that have been expressed).
- Increase the cost of building additional generators: I like this mechanic but its impact is not so noticeable. It needs heavier price hikes to achieve the effect its designed for (preventing opponent from snowballing their economy quickly).