Following my previous comments, I'm here for more feedback and tests :
- I've added the "bCanHaveBound=true" to assault and tinkerer classes : now the soldier bounding button is no longer greyed out (and seems to function normaly ; I've haven't however had yet the occasion to bound new soldiers again).
- I've seen (and corrected) some localization mishaps : the return fire, quickdraw and lightninghands abilities are bound, in the base game, to the secondary weapon, which makes sense, for sharpshooter or templar, but here, for example, with a ranger, the text will mention the unit sword. So I've updated the XComGame localization file on my end to replace the "secondary weapons" mentions with "pistol" for these abilities.
- I've finally understood why my reaper could equip a pistol as well as a sawed off shotgun : her squaddie perks contained on fact two sidearm perks (in my case one for pistol and one for sawed off shotgun) ; was it intentional, though ?

I've also remarked that the squaddie perks don't seem to appear on squad select (when using robojumper mod) : it could be great to see at least the sidearm perks (which I tend to forget between my soldiers), but I've no idea how to do it.

Reapers get 2 sidearm perks at Squaddie yes that is intentional. You can set 'show squaddie abilites' in the MCM options for Squad Select.

I didn't even know that, thanks.
On an unrelated note, I had the occasion to bound an assault with another soldier (after my bCanHaveBound correction) and everything went as normal.
Otherwise, this classpack is really fun to play with :D

After a lot more playing, I'm back with more feedback :
- Assault and tinkerer do not seem to gain any individual AP
- I'm not sure if it's intentional, but it feels a little strange that rookies and keeper cannot use SMG (I will probably add it to my personnal configs).
- The assault and tinkerer have low resolution icons, which is especially visible in the guerilla tactic school (though it doesn't impact the gameplay ; I'm clearly nitpicking here)

I've found another strange behaviour, but I don't know if it is related to this mod himself or one of its dependencies :
Tinkerers have been assigned a NumInDeck of one in the XComClassData ini, so I expected them to appear four times less often as regular classes. But, in my playthrough, they appeared instead as often as the others (through random promotion).
I've just tested with only thismod and its dependencies active through debug mode (even regenerated my config inis) and the behaviour stayed the same.
The same can be stated about assaults, which are meant, in the ini, to appear two times less often as regular classes. It seems the NumInDeck values are not taken into account by the game and I've no idea why.

I've also remarked that keepers can't equip PCS, but haven't tested yet if it comes specifically from this mod (I looked at the corresponding *.ini but didn't see anything strange) or if something unforeseen is happening because of my current modpack.

I come back after a while but I've since then found why keepers couldn't equip PCS : in the XcomClassData ini, at their fourth squaddie line, there's a missing parenthesis : "(), \\" should in fact be "()), \\"
I just tested the correction and now they can equip PCS as intended.

Thanks for spotting this will fix when home

While I was at it, I tried to investigate the oddities concerning the class spawning (their appearance probabilities not related to their NumInDeck value) and, to my surprise, it seems to be vanilla related. My test was as follw : I deactivated all my mods, and considered the vanilla specialist case on strategic debug start :
If I put NumInForced =0 and NumInDeck=0, I don't obtain any specialist when I level up my soldiers (as intended so far). However, when writing NumInDeck=100 (instead of 4), specialists do come back, but they represent always 1/4th of my promotions (and do not become preponderant).
Something is clearly off here (it is has if the NumInDeck value has no impact, granted it is strictly positive), but at least it has nothing to do with your mod or its dependencies

NumInDeck needs to be weighed against all your other classes. It is literal "cards in a deck".
If classA has a NumInDeck=1 and class B has a NumInDeck=99 ... then out of 100 soldiers you will get 1 ClassA and 99ClassB ... until the deck is empty, and then it will 'reshuffle'

@RustyDios That's what I thought, but not what I manage to observe so far (even with all mods deactivated and after having cleaned my inis). With my example, if I change the NumInDeck from one specific class (the values for the others are left unchanged), it doesn't change its distribution (granted NumInDeck stay strictly positive, of course), at least in strategic debug start and using the command "LevelUpBarracks" I'm using for testing.

@RustyDios After a lot of tries and dwelling into the code, I might have found what was going on :
There's apparently a config, in XComGamedata, named MaxSoldierClassDifference, and initialized to 1. From what I understand, it is used in the XComGameState_HeadquartersResistane and XComGameState_HeadquartersXCom to prevent rolling classes that have already been rolled too much (so that one does not roll 4 rangers in a row, for example, even if it would be possible with the default NumInDeck values, I suppose)
I tried to change this config (and put an absurdly high value, 1000, so that it doesn't have any impact anymore), and for the first time, I am rolling only specialist (I am testing again with my previous example), as soon as the forced deck has been depleted.

*almost only specialisst, to be precise. I have kept the other classes at NumInDeck at 4 and changed specialists at 100 for my testing, so I see one of them appear sometimes, albeit rarely (which works exactly as intended)