Never had any issue with controls in this game.
If you have trouble jumping, maybe you didn't realize that he jumps towards the direction where you did the up-slash, ie up-slashing to the bottom-right of where Ryu is will make him jump exactly towards that direction where you slashed.
I have gone through all the difficulties and pretty much never did any wrong move by acident (maybe in the first few moments when i was learning it, at most) , and the touch also makes it incredible easy and fun to target arrows and bombs at each foe you want. It wouldn't be so efficient if it were d-pad controlled.
It's a repetitive game indeed, but so are all beat-up up games, it's part of their formula to kill, kill, and kill non stop, and when the playability is fun, it's not a bad thing.
Also, hands up for the challenge of last mode... The AI is incredibly buffed and you will have lots of trouble dealing even with the small critters since they gang-bang, dodges and counterattacks you so much.
PS: Games like Nanostray, Soma Bringer, Etrian Osissey, Monkey Ball, Resident Evil, Viewtiful Joe, Princess Peach, and so many others, being called horrid, is ridiculous...
If you tried all those games in most underrated thread and finds them all HORRID like you said, please, sell your DS right now, it's not for you.