Hey hey don't talk like that D: I feel discouraged with Brawl a lot. Heck even with other games I just feel like I get nowhere sometimes tbh.
Imo the best way to improve is to try to NOT improve.
When I first got UMvC3 I was just playing around and learning the characters moves. Basically, I was excited I got the game and wanted to learn the characters, not the 0-death combos. And when I played people that had the game MUCH longer than me, which they did better combos than me, I tended to get more hits.
But after a while I started trying to learn the metagame of it and my win-loss ratio went down DRAMATICALLY after I started learning combos and tactics and stuff like that. I wasn't exploring the little gimmicks of the game anymore, I was exploring top-level play, which focuses more on lengthy combos rather than practicability.
I started doing the same thing with my brawl game and I think I've improved leaps and bounds. Went into training mode and just started learning the feel of the characters instead of using their best moves or tactics. I also just overall slowed down my gameplay so I could focus on what I was doing and what I could be doing instead of what I needed to do in the situations I put myself in (lolaggro).
I would just try to stop trying to win and play slower. Hopefully that helps.
Also I feel like I wrote some huge long paragraph @___@ hopefully I didn't flood you lol.
We should play again sometime :D