I never bothered with the DLC for OMD - didn't seem necessary. More levels, though... I felt this game was short (in part due to my distaste for the enemy ramping in endless) so more levels may entice me. More enemies and/or traps, though, is less interesting. I already have too many I haven't used once. Though a mode that allowed you infinite weapon slots would be entertaining. I'd love using it to discover new combos.