That looks like a lot of work!
I hope you frequently tested this file between editing it.
Panzer Corps trouble shooting and searching for errors can be quite frustrating.
At least based on experiences with my own "Locarnus Addon" mod, as well as trying and so far not always succeeding in helping others with trouble shooting.
Transport categories game engine limitation - IMPORTANT!:
Speaking of pitfalls with regards to the equipment file, the transport category limit is one of those.
I forgot the actual transport category limit (was it 30?), but bad things can happen when you exceed it.
So I highly recommend you trying to consolidate those where possible.
Eg "bonus" units do not need different categories from normal units, since there is no overlap between bonus and normal units anyway.
Thus your currently 3 categories t1, t1se and t1s can be reduced to t1 and t1s without changing functionality. Simply replace every current "t1se" entry with "t1".
Ground Units:
I find the concept of stronger "non-bonus" units enticing.
Though I struggle to think of a way to balance the clear advantage due to the 1 unit per tile game engine.
Taking the AMULET unit mod as the example for it, I pretty much always preferred the better unit stats.
Especially for units that are unlikely to take damage, which makes the increased prestige cost a one time consideration.
For my own mod, a major issue was, that the player does not have direct in-game access to all the information of the equipment file.
Specifically regarding the upgrade families, switching opportunities and eg rate of fire stats.
This game UI limitation made quite a few of my modding plans not feasible, if I wanted to keep it accessible for players who do not look at the equipment file directly.
Air units:
I like the unit variety, eg for playing with my house "rule of one" (only having max one core unit of each unit type version, eg only one Bf 109 F-4).
Some of the availability dates might need another look (eg Bf 109 G-2 to G-6).
Experience boni (exp.pzdat) balance effects:
Another major issue I faced for my own mod, was the effect the experience boni have on the unit balancing.
Many classes receive a higher attack bonus than defense bonus per experience level.
With the way the game engine works, this makes combat more deadly, the more experience the involved units have.
This is imho the main reason why the vanilla game balance feels so broken, the further the player progresses in a campaign.
I tried two approaches for my own mod.
For air units I compensated those imbalanced experience boni by increasing the base defense stats more than the base attack stats on later units.
For the ground forces, I leveled those skewed experience attack and defense boni in the exp.pzdat file directly.
The first approach might have some fringe balancing benefits, but also considerable drawbacks and is a real pain to work on.
The second approach is so much less straining, both on the modder and on the player.
Oh, and some unit traits are obsolete and do not have any function anymore in the equipment file:
close, alpine, rott, fixedt
Best regards and good fortune with your mod,
Locarnus