I love the final color scheme for your mount! The stripe design on the belly is great! It feels weird to me that the stripes on the neck are a completely different scale than the ones on the belly. It feels like it could work if we saw a transition from thin stripes to thick stripes in the area between, but that in-between lower neck section matches neither the top nor the bottom, so it looks a little like two or maybe three different creatures welded together.
As for Miaseeli's costume, they're all nice. By itself, the last one is my favorite... But it's probably also the one you should not use. The big test should probably be what she looks like on her mount's back or in front of her pet (whatever it is), as you wouldn't want the two characters to blend together. You might even consider throwing in some totally contrasting color on her to help her pop. You used a blueish teal earlier on the creature, for instance: What about that color for her cloth?
Anyhow, just some ideas. Great work and good progress. Good luck with the rest! 
