Haxball

Your strengths and weaknesses may never change, but they will still get better as you do, albeit disproportionately of course. You're bad at jumpstream, so just play jumpstream files. Play them for hours. Play ones you have to struggle to SDG, and play ones hard enough to make your hands and arms burn. Then play them some more. Then, the day after the next, play them again. If you aren't already doing this, you can't say you're stuck. Plateauing doesn't really exist, if you aren't improving it means you haven't put in the effort needed to improve, or your effort has been misapplied. It's more of a problem at really high levels, but never totally concrete.