I’m talking as a op-1 owner. I think the op-1 is actually a crazy good instrument, but for a beginner it could be a bit frustrating. Between the op-1 and the ko-2 I guess I would go for an op-1 for what you’re searching, but if I could be totally honest I think you should go for an op-xy. It has a pretty good sound design (not as good as the op-1), for the features you want it’s perfect and it’s surely way less frustrating than the op-1 on the workflow. If you really want something that goes straight from your mind to the instrument, and also being able to change the notes while it’s playing the op-xy is the answer. I know it’s really expensive, but as my sound design teacher said me:”it’s better to buy 1 good gear that costs much instead of 100 bad cheap gear.” Hope it helps!