I don't know if it's possible to add wallbreaking(if you switch the action to CA_GLIDEANDCIMB, he wouldn't be able to double jump near walls).
Maybe what could be done is to force spin for 1 frame, or Jet can spawn an object which busts those specific walls. It's true that he can complete the official campaign as is, but in order to do so, he needs to use the oil factory passage in ACZ1, and if he uses the starting right path in ERZ1, he screws himself. Additionally, the inability to spindash may screw with his compatibility with custom level packs.
His normalspeed is slower than sonic's, thrustfactor is the same, accelstart is way slower and acceleration is a bit faster, same like knuckles. He doesn't have a higher jump than sonic, it's the same.
His ability is the double jump, which works well because he is a bird that can't fly.
His stats aren't the source of his speed, the dash is. I don't have any problem with that, he's obviously meant to be a speedrun character, but he doesn't need such good jumping capabilities if he's also going to have invincibility frames. You must not have tested his jump, because it's definitely higher than Sonic's. Jet's cool with a double jump or a boosted jump height, but not both; it gives him too much safety in combination with his invincibility frames and lets him access routes that clearly aren't meant for him (AGZ's Knuckles path is a good example).
Boosting isn't op if you compare it to the spindash:
Both give you "invinciblity" while using it(the boost gives you the invinciblity, like invincibility powerup, which should be changed so it's like the spindash)
Spindash gives a lot of speed if you charge it, you can use it any time to roll.
Boost can be activated at any time and gives you speed, but you can't use it forever, it's only for a few seconds.
The spindash's damage ability is not comparable to boost. Jet can use the boost to dash through enemies, projectiles, level hazards... Invincibility in general is pretty damn powerful, the only reason it's acceptable here is because there's such a short frame to use it in between cooldowns. Speedwise, it's a clear upgrade from spindash, because you can boost then jump to give yourself constant speed. It's basically the equivalent of a ground thok, and then you have an actual jump ability on top of that.
If you think the boost is balanced against the spindash, change Jet to use spindash instead of the boost, and see how long it takes for Jet to beat the Metal Sonic race. If you're playing right both ways, I guarantee you the boost Jet will beat the everliving snot out of spindash Jet.
For the record, I'm not suggesting dash be nerfed, because it's a cool ability, and Jet being centralized around it makes him interesting. I just want to see his jump balanced around that so that the main levels aren't so easy.
Not all of the sprites are finished and they are still the old 2.0 ones.
That's fine, just replace the ball frames with one of Jet's fall or hurt frames or something. I just don't want to see that ugly meme in my face whenever I'm in a zoomtube.