As I'm not really following much of the New Canon, mine is really only gonna be those who haven't improved/become worse off.
Damaged
Boba/Jango= No longer Mandalorian and thus far have been....ehhh...especially Jango who's only real great feat thus far is 'fighting' Obi-Wan, if that.
The Jedi= I mostly blame TCW for this, the Jedi just haven't been impessive apart from the handful of showings we do see and it's mostly involving the main characters(IE: Anakin mostly), I'm not asking for any crazy feats, but even those for the most part I'm recalling that they just seem underwhelming.
ARC Troopers= HA! What a laugh these guys are...
The Inquisitorius= I am really sad that these are the Inquisitors that most people are gonna know now. I find them...kinda bland, they all pretty much wear the same attire, using the same lightsaber apart from the 10th Bro for some reason.
The Mandalorians= ....They became pacifists...enough said.
Derek Hobbie Klivian = They killed him at the Battle of Hoth....
Han Solo= What I've seen of him...no...the guy even got outdrawn by a damn drunk....a drunk.
Stormtroopers/Imperial Army Troopers/GE as a whole= ....Thank you Rebels.....thanks for going with the stupid memes/ignorance and making it Canon. Thanks for doing away one of the aspects that made the GE unique compared to the other factions by getting rid of their 3rd branch.
The TIE Defender= Well...let's make this awesome fighter annnnnnd...it's gone. Again, thanks Rebels for taking one of the most awesome starfighters within SW and have it only be in like...3 episodes..