What do you think of Power Armor becoming its own type of unit; heavier than infantry but packing two weapon slots, having more maneuver, and possibly being able to drop/board without needing special transport bays?
As it stands currently there is nothing very special about power armor other than it provides some extra armor to your troops. This fair, obviously, but pretty unexciting and not even the main draw of a self-powered military suit. What drives power-armor development IRL is its ability to give its user enhanced strength, speed, and endurance, with extra protection being a minor factor if it is one at all. Good Power Armor imo always has integrated features that distinguish it from a mere suit of armor, like integrated weapons, targeting software, jetpacks, and so on.
You could easily replace the current +1 armor PA with generic 'Improved'/Advanced Armor' upgrades. I already rename it that in my head since I hate the idea of every grunt in the army getting their own set of Heavy Power Armor once the economy allows it. PA units should be elite, costly, difficult to train, and make up the specialized core of your army where you need low numbers to do a lot of heavy lifting, like with boarding actions or taking outposts.