This is a petpeeve but i really hate this minimalistic look that permeates EVERYTHING nowadays. They coulda have simply made this new UI without getting rid of the art that made the game iconic. Better, they coulda make a lot of cool borders for the UI with themes like Horde/Alliance/Racial themes. Instead, it looks like a mobile game.
I guess it fits with my Windows 10 having only a black bar and a white windows logo. Really, what the hell is happening and why are companies growing allergic to visual identity that has more information than a white sheet of paper? Bring Windows XP visuals back.
All that being said, if i ever get over my loathing of Blizzard enough to come back, i really wanna make a soloing Shaman. The new talent trees look phenomenal. I thought about playing a DK too, but DK trees look kinda uninspired. Shamans got lucky, i guess.