2) I'm done debating this point for the millionth time. You logically can't balance the game for all players because unit and faction strength are completely dependant on the player if you assume non optimal play. There would be a million unresolvable conflicts as proven by this forum.
Surely you can't do it to 100% but you have to take players seriously about units that just perform way too good at lower skill levels.
If you construct two factions for example:
1) Faction A: units are sturdy, expensive and pretty straight forward
2) Faction B: units are glass cannons, versatile and mobile, maybe a bit sneaky
I predict Faction B is good at toplevel play, maybe too good. Faction A will lead winrate at lower skill levels. Just don't make factions/units artifically like that.
ST is a good example of a unit which is way too good at lower skill levels. Game promotes blobbing at lower skill levels, scouting is less relevant. ST shoots out of nowhere scoring a lot of kills. Just don't make units like that.