4 Factions, A shitload of commanders. I don't know about you, but i have around 15 different tactics to approach this game depending on faction choice and the enemy/combination of enemys i see. I'm far from mastering them all. None of those include less then 5 different units. I like those combined arms. And they do work. And yes, sometimes it takes more effort to punish the blob, then to a-move it. But then again, it brings me uberjoy to see those blobs transform into little xp values floating to the sky.
Try playing Ost and not just usf before offering opinion.
He's right though, I play a ton of Ostheer as they are one of my favorite factions. They certainly aren't the easiest to play or in the best state as far as balance in concerned, i'll admit that. However, I've been having a ton of fun (and success!) using ostruppen against USF. Developing and tweaking that strat to my taste has been really really fun and rewarding, and while it's certainly not as viable as 4-5 lmg grens into tiger, its a hell of a lot more fun to play, and I've maintained my ~150 rank using it. You can totally outplay your opponents unit cluster, it just takes a lot more effort and skill to do so than it does just to a move an OKW unit cluster of doom.
My advice: If the game is frustrating you, take a break for a few days. It also helps to acknowledge that stupid shit related to RNG and balance is going to screw you over some times, but at the end of the day you as the player have BY FAR the most influence on the outcome of a game. If you lost, it is without a doubt your fault.