Painting can only be as good as your preparation... a very ambitious mini to begin with, I would suggest cleaning up all the joints and filling them with a quality epoxy or greenstuff. Practice on some cheap plastic minis first and acquaint yourself with the properties of your chosen 'filler' and tool for application. You can use a multitude of things rather than buying sculpting tools, even a cocktail stick, just keep it damp. On a positive note the blending on the wings looks tip top ;)