1./ I do not think improving just the MG would improve wehrmachts current state. MG42 is perfectly fine as it is.
Well, I'm afraid not. Thanks to power creep other mgs are more self-sufficient and can be left alone without support more often, effectively locking quite a lot of map (UK mgs are just crazy in this respect). Mg42 needs a spotter or will be too easily flanked or even rushed into its arc of fire and killed head on (it happens too easily in later stages of the game with more upgraded/better infantry). The problem is that with very mobile allied units it's practically impossible to keep babysitting mg42 to such a great extend mid-late game. With other mgs you need less babysitting as they react to threats more autonomically. Secondly, ost infantry don't have that many tools to clear mgs. They are slower dealing damage and don't have that many smoke options. Yet, they get pinned further from allied mgs and lose models more quickly when under mg fire. If you don't like the idea of making mg42's vision similar to say Soviet mgs (I'm not even trying to suggest UK's los), maybe other mgs should have shorter los - identical to mg 42.
2./ The Howie is very devastating. I think nerfing the damage and increase AOE will help a little or just nerf the damage. That I agree on. It is extremely powerful. One of those is equivalent to 2 mortars firepower. It is just that good. I think wehr mortars needs to shoot a little faster. Howie shoots at the same speed.
Agreed. Still one thing to be remembered is that most ost units are stationary and predictably tied to cover. Comparing allied indirect fire options and ost is just difficult, as the impact of such wweapons on ost is huge while allied infantry is mostly on the move, so unless you make some mistake of just standing for a long time in one spot, they are tactically almost immune to indirect fire. Fun fact is that pack howie dmgs units on the move which ost mortar should do.
3./ It is not a bad idea. I would rather improve both the engineers and pioneers for both SU and WEHR. Make it fair and square. It is a good idea tough.
Agreed. I still sometimes think that going for fourth bunker option (repair) is good because pioneers are overworked anyway. They build base buildings, lay mines, clear mines, need to help with assaults, build sandbags and repair. So speed, yes, but also you need to let them do other things as retreating sometimes 200 or even 400 manpower from the front to repair a tank gives your opponent too many tactical advantages. Not to mention the fact that sometimes a good tactics is to concenterate fire on you pios and ost tanks are dead.