Jade has been mostly fine, most people just wanted her to play a certain way and since she doesn't play that way it irks them. She's literally the Doomsday equivalent of a lame character. She's good at what she does and really basic and like Doomsday generally doesn't do much damage.
A lot of people want to use all her staff strings all the time, stuff like that is mostly for checking people or whiff punishing a wake up or out ranging people because while others have twelve frame mids with the range her ten frame staff attack can really swat people like Baraka away like a fly with optimal spacing. Anyone that complains about Back 3,4,3 doesn't understand the utility and how much better of a staggerable mid it is than a lot of mids considering all she can do at a distance too.
People are writing off her forward 3,4,3 string too, it's great when you have to play up close since it is safe at all points, starts as a low and is great for stagger pressure. Combine that with her short hop overhead, throws and back 3 and you will be cooking. Forward 3 on hit is plus 16 so the opponent has to guess if you're gonna go for strike or throw.
Forward 2 string is just to make people block high so you can wiggle stick them in the mouth and of course if you happen to get a combo, even better.
This is basically the core:
Back 3,4,3,4
Back 2
Down 4
Air glaive
Edenian Spark
Forward 3,4,3
2,1,2
Down 2
Sweep
Shadow kick
You're good to go more or less.
I'm content with her, people have been overthinking her. I don't think she needs to change. If people prefer a different play style, you might just have to play multiple characters to get your fix, but she really is a well designed character right now. 16Bit has insisted for quite some time that Jade is good as well and reiterated that at Combo Breaker while on commentary and that's probably because he embraced the lame. Her walk speed is fantastic and back dash cancel with her for supreme lolz.