Visual design contrast and readability
I'm glad that this new version didn't ditch the email tabs. That is the primary reason why I still use Y!Mail after all these years, and it made me crazy that past redesigns would try to get rid of this critical feature. I'm still getting used to the new layout.
But the lingering issue is that this new visual design makes it hard to read the content. It feels like all the words are harder to scan and read. It is definitely much harder to see which of my emails are read or unread in my inbox. The airy, pastel color scheme just doesn't give my eyes any purchase to latch onto. This isn't so much a problem of the words IN an email. It's the words in the entire functional app: the email details in the inbox like subject, sender, the folders along my left nav, just all of the chrome of the app. Once I'm in an email it seems to be fine, but it just overall feels harder to scan Yahoo Mail as a whole to navigate. I need more contrast.