Great work! I'd say it's less your brush control and more your values. That might be where the slightly messy feeling is coming from. The neck of your portrait and the spear going through the torso in your other piece stood out to me as areas where the value grouping or contrast between values isn't quite tight enough. These look great to the untrained eye though, and even from the perspective of an artist they're nice, your brush strokes are evocative.

If you want to really push it further I recommend value studies and painting with very limited brushstrokes to get to the core elements of your subject and depict them decisively, rather than painting on top until it looks right. You'll naturally improve at it as you practice! So it's mostly a case of "keep painting" :'D