If you lose a lot to the practice computer, it will eventually get much weaker - lose resistance, HP and other things until it's very easy. Then it's level will lower, until it gets to 25, the lowest. When you beat it again it will become increasingly stronger, and so on.

I think there should be difficulty settings on the practice mode, for example EASY, MEDIUM, HARD, VERY HARD, INSANE - and increasing rewards depending on the difficulty. Maybe "EASY" gives 500 SM and "INSANE" gives 3000 SM.

Also, there should be a bonus prize for completing campaign, maybe a color kit? Or a SM bonus. Because at the moment, there's very little incentive to do campaign. You get more money from doing PvP.

What Ogonna said ^^^