The hardpoints limit thing is kinda hard to figure out. As far as what it is exactly, it's definitely not the max number of combinations, because the 47N has 4x6x5 possible combos. Not the number of objects either, because the Ju88 has 20 in a single bombload option. It might simply be the number of options you can click on/display in the hangar, because at a glance the highest I see is 15 options on e.g. the P47N. There'd be much more than that with one 410 model, if we wanted to have as many gun options as possible. Quick a dirty simulation of the 410B in AH's hangar is something like this, ignoring the bomb options in the bomb bay for now..
Ordered by firepower.
Since the A model never had the B's large choice of guns, it might make sense to, in a hypothetical AH, give the A all the bomb options that wouldn't fit with the B (which is pretty much everything except the vanilla B1). The A model reportedly could carry all of these:
It's not clear if any of those bombs went on the wingroot racks you can see at the top right in this pic:
Working it out so that the 410A would have as many of these bombs while leaving as many gun loadout options as possible could look like this:
Which covers all the bombs and gun options in 6 choices, which is convenient because that's exactly how many you can fit in one AH hangar column. It also gives an option for nothing but a BK5, which might be worth it for the weight saved: The BK5 is ~1000lbs without its ammo, a pair of MK103 (410B-2/U4) and their ammo weigh ~1000lbs, and a pair of MG151s and MG17s and their ammo add up to a little over 600lbs. That's the difference between the two choices at the bottom of the above pic.
Everything else - the drop tanks, WGr21 rockets, and 4x50kg bombs - goes on the wings, so there's no conflicts there. All of these guns, ordnance, and everything else together add up to about 10 options, so there's no risk of breaking the 16 option limit.
So that answers your question Karnak
This is with just a generic A and B model. If HTC just make duplicate models to "create" Me410A-x and Me410B-x variants (like we have for the 109Gs), there doesn't seem to be anywhere near as much complexity to figure out for each model. There's no apparent differences between the A and B in the literature, so in the game the differences between the A and B variants would only be the guns. So maybe HTC could just call em 410A and 410B. The only benefit in making different A1, A2, B1, B2 models would be historical accuracy (hair splitting in this case), and 30 more skin slots. There's already 30 of em with a generic 410A and 410B.
There were also some other loadouts on the B5, which I'm not sure whether it was more than an experimental model:
- 2 BT 400 bomb-torpedoes
- (up to) 6 BT 200 bomb-torpedoes missiles
- 1 SC 1800 bomb
- 1 LT 5b torpedo or 1 LT 5i torpedo
Were also tested on the B5:
- SB 800 RS (rolling bomb)
- SB 1000/410 low drag bomb
- L 10 (LT 950) gliding torpedo
The B2/U3 also carried a single torpedo along with a pair of MK103 and a radar in place of the nose MGs. That one was certainly operational.
Apparently the A2 was cancelled because the MK103 wasn't ready. Not sure if that means the single BK5 armament (A2/U4) as well.