I started doing 3x3 one handed from the start, before I even knew it was a separate event. It just seemed like a good idea for training the hands and making my moves more deliberate. The puzzle progression was:
3x3, 3x3 OH, 2x2, 4x4, 5x5, 6x6, 7x7, 8x8. I haven't had any interest in non-cube puzzles yet. Maybe eventually. I'd like to try BLD, though...I am just having too much fun with big cubes to sit down and learn something new.