I like the way you play Samus. I haven't really seen a vid where you have had your weaknesses exploited so it's really hard to say what you need to work on. Based on the videos I have seen though you look like a patient player, you use your projectiles well, and you look like you punish behavior rather than just have a "bunch of stuff you do"
At your point I don't think there is anything specific I can say you need to improve. If you feel like you're at a plateau you need to play with new people, that way you get exposed to different styles and can adapt yours to work vs it. Also be sure to record (or use that hack that gives infinite replays) so you can study how you do in different matchups, stages, etc.