For me it would be discovering what I think is being dubbed a “recall-evator”, where you take two objects, lift one up with ultrahand, stand on it, recall it, and lift up the other object at the same time. Then you can alternate between them, recalling and ultrahanding as far / high as recall will record. I used it to lift myself over a wall blocked by a puzzle in one of the shrines - it is a bit tedious but very busted.