Re: Engineers VS Fortifications
 

I could be totaly wrong as I observe what happens & make judgement calls rather than test but in my view.

Vehicles bunkers & quite possibly infantry to a lesser degree are more susceptable to an attack if badly suppressed, routed even worse.
Yes they have less more inacuate shots but that is not what I am talking about.
The game also factors in IMHO the fact that someone can slip through the net as they are now not very observant.
Taking vehicles bunkers.
Attack a good order one with a handgrenade & the chances are nothing happens.
If its suppressed or better still routed that handgrenade might just do something.
If its damaged as well you now stand a good chance of it going bang.

Thats why the first attack often fails but if you assault twice in the same turn the second will often get it. If it does not & its routed the next will no matter what the weapon unless you are very unlucky. Because they just strolled up & placed it nicely because no ones looking.

In early WW2 often this is your only option to take out a tank as you have no inf AT weaponary so you swarm it, well so long as they dont decide to run instead.

I would say routed troops die easier to & so probably do pinned ones as it seems common throughout the game.
A decent experience vehicle crew will try & evade an ATGM it sees coming but not if its buttoned for instance. High experience troops seem to take less damage from fire because I assume they do the same to simulate using cover better & pass the die roll more often.

I could be totaly wrong but the combat status of a unit seems to play a large factor to me. Experience does to as not only do they shoot better but they evade better till pinned at least making high exp vehicles very worth while vs SAMs ATGMs.
Your proposed exp boosts for air will be more than worth any extra cost not because they shoot see better but because they evade better & will often slash the SAMs to hit chance by a 1/3rd or more.

Re: Engineers VS Fortifications
 

Not so much "more susceptable to an attack" as likly to recieve more damage from a sucessful attack due to their state of supression.

And while it's true a supressed bunker isn't going to shoot back es effectively, or possibly at all, it can still take many many turns worth of attenpted assults to actually destroy them.

I rarely see bunker crews route...it happens...but VERY rarely from what I've observed. Perhaps it has something to do with my unit being adjacent causing the crew to not bail out...no idea...

Morale and experience definately are a factor but I was looking more at the "base" chance rather then any specific modifications due to nationality, equipment, morale, experience.

Re: Engineers VS Fortifications
 

Only stating what I see to be honest had no idea engineers got an assault bonus at all but from when I first start attacking a bunker with a view to killing it barring outside interference I would expect it to be dead in 2 turns. On occasion 1 will be very resiliant but some fall straight off to. Using regular troops it can drag on but engineers have no problems dispatching reasonably quickly. The hard bits getting them there in the first place & keeping them in good order for a solid attack:D
No they dont route often but if its being problomatic you can force the issue & because you are adjacent so probably have cut off its escape route it often just surrenders.

If you just attack a bunker with one unit each turn & no support it gets to attempt recovery between each attack so any suppresion could well be mild. If you hit it hard on the first turn or even before going for the kill one attack will probably keep it heavily suppressed.
Applies to any attack hit a unit hard enough that its heavily suppressed & all you need to do after is take a shot at it after to keep it that way.