Joss Whedon will straight up disappoint you if you give him enough time. Happened with every show/film he ever did.
Buffy - after season 5, that shit was off the rails stupid
Angel - After season 3, really hit the wall of dumb
Firefly - barely got off the ground and when it did, they killed it
Avengers - was cool the first time I saw it, but hard to get through the first 30 mins of Zzzzzzz and then the way it ends is ultimately stupid
Joss Whedon. Heartbreaker...