1. How does your muse usually walk?
Almost awkwardly, due to how her legs and hooves interact. Walking around on one’s tippy-toes is fairly similar to what her gait is like (from an anatomical perspective, she has a cross between plantigrade and ungulate joint structures, hence her odd walking pattern).
10. What little things their friends do that annoy them?
Well, I can only answer with general things here since specifics will probably change from person to person.
The first is that a number of friends have (and probably will) insist that she is a good person at heart, and look past the terrible things she has done. She almost certainly finds this annoying on some level, as she herself can’t quite wrap her head around such claims.
Another is when people go out of their way to help Amelia in the human-sized Noxus (or other places not designed for her kind), due to her stature. This is more of a embarrassed-annoyed way though, and she does appreciate such things regardless.
11. What little traits they themselves have that might annoy people around them?
Well, her addictions could easily be one depending on the person. Related to the last one, her tendency to put herself down could also be a point of contention between her and her friends.
For more goodly-aligned friends, her lack of morals may very well be something that could annoy those close to her.