One mod I'd like but apparently doesn't exist is to group my troops into squads. I have a team of "starters" who I like to send as a first choice, and having to manually pick them every time can get tiring. Instead I'd like to just select "starters" and have those six immediately show up. And then I might have my "second team", my "tech heavy team", my "SPARKs team", etc. Of course I will often need to mix and match based on injuries, fatigue, the specific type of mission, etc, but being able to pick them all at once would've been nice.I'd really recommend taking a deep dive on the Steam Workshop and trying out some of the gameplay-altering mods rather than trying to slog through a run on the highest difficulty of the basic game. There are full overhauls of the character classes, gear, psionics, MECs, enemy AI, enemy unit types, and basically anything else you can think of as discrete packages that you can use to fine-tune the experience in - IMO, at least - a much more interesting way than doing a Long War run in the first XCOM.
I just started a new run and I've giant pile of mods running. It's basically a totally different experience with new challenges that don't just amount to more enemies and bigger health pools.
But based on my research apparently this isn't possible without going on a deep dive into the game code, like what Long War 2 does.