Not really a fan of Rarity’s redesign - generally she looks somewhat fragile. I much prefer the old look with the boots and white blouse.  
Same with Sunset. Her new look is okay, but her previous two looks - especially her EG/RR appearance - will always be my favorite.
 
Rainbow however looks much better. I can’t imagine how she could possibly be a jill-of-all-sports-trades in those huge boots and tight clothes.
 
Fluttershy’s look is an improvement. The previous tank top and knee-high boots don’t really sound like her kind of thing, and while the sandals are much more fitting, they seem rather overdone.
 
Sci-Twi has been redesigned pretty well too. Replacing the clogs and frilly skirt gives her more of a sport-oriented and intellectual look that doesn’t necessarily come off as nerdy.
 
I can’t say anything for Pinkie or AJ as I haven’t reslly followed their redesigns.