What I liked: Due to the teleport arrow Legless Knight requires a lot more tactic than other similar rouge likes. You need to think about where you are going to move well before you actually move. You can't just run and gun, hope for the best and run away right when danger presents itself. Skill based movement is something that has been lacking from the rouge likes I have had a chance to play. I think it adds a lot of depth and planning.
What I would suggest: I only had two issues that i can think of; The play area felt a bit cramped and enemy's projectiles where a pain. I think if shooting gave a little knock back you could scoot around small projectiles like arrows without completely giving up your position. Different enemies could shoot large projectiles that are too wide to be dodged. Additionally you could add enemy projectiles that can be shot down before they reach you.