He's fine. He's a gamer, he can make all the throws from the pocket. His accuracy is spotty - he's a "streaky" player who will have Fitz-like games/months of staggering inaccuracy where you wonder what the hell is wrong with the guy. He's played at his best in highly detailed passing offenses with well-defined reads and specific coverage beaters designed by the likes of Shannahan and McVay. He can't elevate the team around him like Brady or Rogers - he's really more of a system guy. He's not athletic. I've never seen Cousins make a play and thought to myself, "Wow, no other QB could make a play like that." To my mind he's a lot like Tyrod but the inverse - they're both in the "middle tier" of NFL QBs; neither can win games on their own. Cousins (unlike Tyrod) can operate a traditional NFL passing offense but can't do much if you take away his passing weapons or put him under pressure. Tyrod (unlike Cousins) doesn't need too many weapons and can change the game with his legs and unpredictability, but can't operate a rudimentary passing attack.
Basically we're getting rid of one form of "meh" QB for another - PLUS TWO FIRST ROUND PICKS. I'm not kidding, I'll stop watching them.