Caches and bunkers can be killed with Captain alone, Schwerer is taken down by combined arms. You basically have to commit almost all your forces for this task, leaving you vulnerable with map control and flanks.
Losing your Schwere Panzer HQ comes also with a major setback, yet a lone unsupported Schwere Panzer HQ just scares single squads off. You certainly don't need all your forces to deal with it, but using all your forces, makes you enemy also using all his forces to counter your attack.
All I'll say is I wish Major, Tankovy Batallion Command or Battle Phase 3 could defend about 10% of a map.
Faction feature. As I stated, vanilla factions need also cool features.
Like you said, defending. It requires some action. For OKW it's "put schwerer in good spot and forget". Pure braindead.
You can't make bunker, plant demo or put mg and forget.
You have keep eye on it, control it, switching MGs positions, bunkers must be on open area to be effective, you have to watch if enemy is walking over demo etc.
With schwerer you can just forget about it and push for enemy's fuel, while you know he can't send 1-2 units to cap your point while OKW blob is punishing everything.
It's obvious advantage that none faction should have.
So now it's suddenly about the micro and not anymore because it denies capping? Your turncoat style argumentation becomes really boring. Likewise you don't need micro for bunkers or booby traps. And demo charges just need a click - WOW huge micro hero here. Same goes to mines, hugeeee micro involved.
Schwere Panzer HQ needs the same micro as a bunker, you need proper positioning of it, place it in a way that AT guns can't use their 60 range.
It's upon Relic to decide whether it should be an advantage that none faction should have. And state of the art is that Relic says it should be a threat on the field, because OKW should place its buildings on the field. Thus they should have the advantage.
Everything can change in two weeks, but this is how it is right now.