An unorthodox practice technique is to make something more difficult, then the “normal” way seems much easier.
For instance, if you were working a standard tremolo, pami, you could practice more difficult variations: pima or do a five note “flamenco tremolo” piami or pmami, etc.
You can also forcefully overplay a piece–pressing down really hard with with left hand and playing very loud with the right–after which the normal way will feel much more effortless. You can also do the opposite: underplay it, very quiet, restrained, trying to make it feel as light as possible. Then there’s shifting rhythmic accents emphasizing different fingers which is useful for bringing out different lines in arpeggio textures or just messing with your head a bit to create a more even sound in a piece.
One of my favorite things to really nail an arpeggio pattern down is to do crescendo/decrescendo work on it. As it start quiet, then grow in dynamics, then shrink back down all the while keeping the tempo constant. Trying to do that at concert tempo is crazy hard, but the pattern feels amazingly secure.
Just some food for practice though. In performance, however, the easiest and simplest methods should be used. Performing is hard enough without difficult fingerings.