I will also admit that I am horrible at this as well. I get my guys to the mid 20's and then get bored and want to try a new build with different skills. I haven't even beaten the entire game yet cause I keep restarting. Its annoying yet exciting at the same time cause you wanna see what you can do with each new character. I also try to keep the leveling as honest as possible and not power-level any of my characters.