So I take it players in the Air Force would be limited to Paratrooper roles?
Well there are no separate Air Force Commanders in the UCCS. That's a CSO thing. The UCCS has only the Council Army and Council Navy. Air Force falls under the purview of the Council Army, as the United Council hasn't really mastered the art of aerial support for the navy yet.
hmm could always have a perk line more suited to supporting other commanders, reserve troops, supply drops, tie them into the air force maybe since much of that sounds more supportive in nature. Less of a direct combat role but great as backup.
That's certainly possible but at the start, air units will be extremely limited. Much of the United Council's air forces and artillery were at the front lines in Southern Aroka and were thus captured by the sudden Grienz advance. What remains is mostly repurposed farming planes, which brings me to-
in a similar line of thinking an engineering based one, perks for field repairs, erecting or tearing down fortifications, adapting civilian infrastructure for military use (assuming any is left standing).
That's pretty close to the one I have planned already. Called Unbridled Ingenuity, focusing on improvised war vehicles, scavenging parts from wrecks, and jury-rigging repairs in the field. The United Council as a whole isn't too big on repairs outside of its colossal war machines (nor on healing for its soldiers!), because for the most part if a single unit goes down, two more can rush in to take its place.
I do have another doctrine (I decided to change the name to 'doctrine' as that feels more thematically appropriate) planned called 'Revolutionary Guidance' which encompasses the old army units, meaning more focus on veterancy than quantity, a mix of the elite infantry units (with an emphasis on urban warfare) plus fomenting rebellion in the civilians to aid in destabilizing enemy control.
So, so far that's 7 doctrines for the Army alone that I'm working on, and I might come up with a few more, plus some Navy ones. I'm creating individual abilities/passive bonuses/special units for each doctrine, things that can be unlocked/upgraded as your rank progresses. Which is why this is taking a bit to get posted. Please be patience, good things come to those who wait!