I did large chunks of Expeditions with a hoplite, sniper, and a tiny bit with a psi dude, before I decided to completely ignore the Black Sea with every character and be far happier for it.
Anyway, I can say, the idea of psi characters having a tough time with strongmen for example is fine since psi is OP, but the result is that it's even more mindnumbingly boring than other characters. Your tactics are always the same, line them up, chokepoint, grenades/traps, then pew pew pew, but the pew pew pew takes 800 million turns and none of them pose any kind of threat. They're MMO enemies trapped in a superb CRPG wondering what's going on.
There's a guy on the official forums who finished UR at lvl 8 on DOMINATING with ARs.
Better nerf quick tinkering again.
lvl6.
Edit: That thread made me depressed because theoretically it means that you can finish the game at lvl4-5 where the main difference is that each fight will be a slog (use traps everywhere, use gas grenades + doors and so on).
Then it shows that there is something wrong with the skill systems because AR lvl 6 can finish the game while the rest of the builds are basically insignificant by comparison.
The AR build is done at lvl 14 with Commando which means that the next 16 levels are pretty much pointless unless you invest in crafting.
You are joking but one possible solution is to increase Traps requirements for traps.
I would argue that almost every build is complete after level ~12 & reaching Core City shops. You can add synergistic bonus feats to top up on your chosen tactic, like more crit power, or crafting perks for super items, but you will not really learn any new tricks. Your guy will play the same way from there until the end. This was true before DLC and is still true now.
Underrail character development has three stages. The first stage is incredibly fun: you're a shitty weakling trying to survive, and you're hunting for the next big tangible upgrade that might arrive by a fortuitous loot/merchant drop, and/or the next feat that really adds exponential possibilities (E.g. setting up for a cryogenic chem pistol at level 6 and going ham on Depot A).
Then you get to around level 10/12, the world opens up, you can hit Core City shops for everything you need, your character is defined and nothing will fundamentally change. It is still great fun for a while to enjoy all your hard-won toys, but at some point you realise you're just doing the same thing over and over again. Snipe+Aimed Shot that guy, force field force field, etc. How long it takes to wear off depends on the person, I guess.
What's the third stage, you ask? Why, that's the biggest stage, the alpha and omega: the 8 hours of character planning before, during and after each of the other stages. Good stuff.