Practice, one thing that you need is plenty of practice.
You can draw, sure. But you currently lack what it takes for animation to really work.
Just drawing inbetween drawings to make movement isn't enough, gotta learn yourself some smears and easing. And as previously stated in the previous review, inconsistent proportions. Yeah, that's a real problem. Very common when you start out, but you'll grow out of it.
You're on the right path, just gotta put that work in so you can get better.
Perhaps trying something different that's something not Game Grumps / Star Bomb related? You don't want to be stuck in a rut doing the same things over and over. Try out new things. Even do animation tests and just keep them to yourself.
Whatever you can do to hone your skills.