I feel like repair speeds have gotten way too fast with the new factions. Nerfing repair speeds across the board to ost/sov levels, with the exception of sturms who can have 1.5x, would add a level of strategy to the game where damaging an enemy's tank without killing it would be more effective than it currently is. Having a tank back at base for repairs should be a tactical element of the game, not a "pop back, superglue together, pop in, go" thing that it is now.
Different factions are good and all, but some quintessential things, like repair speed and access to suppression/mines should be similar or the same across all factions in order to allow deeper play/counterplay scenarios.
You ever feel frustrated watching an IS-2's health crawl up while being repaired by 2 engineers? Good, that's how it should be.
Once again.... repair speeds are faster for allies to help them survive better axis armor by using good micro.