I appreciate the added insight into your argument. I guess that's the difference in our perspectives, I don't see added utility as irritating clutter; I see them as additional tools that help define/differentiate the unit's role.
I have a very less-is-more attitude. Don't get me wrong, abilities are good, they add depth and make things interesting. It'd be a lesser game without them.
But if you
overdo it, you add unnecessary complexity. You make the game harder to understand without making it better. Look at JLI: they're saturated with abilities, but how many actually get used?
Obersoldaten are late-game combat infantry to supplement Volks as they get outscaled and/or wiped. You've already got a whole army of moving parts on the field by then: the game doesn't lack for depth at that stage. There's nothing wrong with them being straightforward combat units.
They've
already got a bundle grenade, a white phosphorous smoke grenade and booby traps. If they're not strong enough, I'd make them stronger before loading even more chaff onto them.