Spoiler:
IDK the finale kind of blew it with DeVoes main power. He's been whooping team Flash all season and had every complication accounted for. This guy is supposed to be inconceivably genius. In the end, Barry beats him by... running really fast? He'll he could have killed Cecile at any moment after Flash went into his mind, and it would have been game over, but he didn't because CIS. Also, Ralph being the only surviving other mind in DeVoes head was kind of a last second ass pull. Everything about the way he went down was a let down.Other than that, Killer Frost was left a dangling plot thread and we never got any explanation tot the symbols Barry wrote in the beginning of the season or why he and Harry muttered the same words when they were simple.
Personally, this season and finale were a near complete let down. The only exception to this was the nuke episode, which is IMO one of the best episodes this show has ever done.
Amunet Black and Elongated Man are also great additions to the universe. I like both their characters.
Also, agreed about Tom Cavanagh. He is by far the best part of this show and always has been.