controller optimality comes mostly from having as much separation of inputs as possible (e.g. trying to keep movement on your left hand and other inputs on your right hand, like x/y to jump and c-stick for aerials and smashes), grouping specific inputs and decreasing travel distances.
so i'd make a case for:
C-Stick for at least aerials, smashes, and roll oos
jump with Y, because Y gives your thumb easier travel to A, B and the C-Stick
wavedash with Y+R, since it simplifies the input into a sort of "squeeze" with your right hand, similar to JC Grabbing with Y+Z
shield with L, to make wavedash out-of-shield easier
L-cancel with L, to load-balance SHFFLs (jump and c-stick aerial on right, fastfall and L-cancel on left)
tech with R to separate it from DI and roll-options on your left hand
however, there isn't alot of consistency among "top-level" control schemes, since honestly the inputs are simple enough that whatever way you learn can work. additionally, there isn't necessarily consistency even within a particular player's control scheme; tons of people will jump with a different button or shield with a different shoulder in specific situations or when performing specific techniques.
imo don't worry about this stuff, because virtually every control scheme is attested by at least one good player. but if you are going to worry about it, think of your own control scheme that's good for specific theoretical and practical reasons; copying a pro's arbitrary preferences is probably not going to be "optimal" since optimality probably wasn't their goal in the first place.
