Alright, I've gone back and reviewed the work I've done regarding character gravity settings.
The only characters I modified that were also in Melee were Mario, Captain Falcon, Marth, and Falco. Of the four, Falco plays and feels very differently overall, so I am going to limit my analysis to the preceding three. I will also provide the code used in the Jump/Grav Values code for each character.
Mario (003865C0)
Mario just feels sluggish in this game. Compare him to his Melee counterpart. Both his jump and short hop are higher and floatier. Now, the full jump height may be alright to leave as is (though I believe it should rise faster), but I don't see why his short hop needs to be so high and floaty. In Melee, he had fast shffls, so why shouldn't he have them in Brawl+ as well? With my current modification, he's definitely closer to Melee, but still not quite there. Still, if people feel they don't wanna replicate Melee Mario exactly, I believe this is a fine compromise. If the problem lies with a certain aerial, I suggest speeding up its cooldown just a tad to make up for this.
Captain Falcon (093868C0)
I must say Falcon feels alright as he is, but nevertheless, he's still no Melee Falcon in terms of pure speed, so I decided to try giving him a further speed buff to get him closer by increasing his jump speed, though again, I didn't exactly match him, since it would require increasing his dgrav.
Marth (116865C0)
I already talked about how slow his shffl game is. This can be fixed with a shorter short hop, making his shffl game faster again. Of course, he still doesn't match Melee Marth completely, as his dgrav is not high enough, but it'll do. And yes, it makes his double aerials just about impossible to do without buffer, and even then it'd be tricky, but a very slight cooldown on his fair would likely fix this problem.
Now, what's holding me back from further testing gravity settings is the fact many characters' settings are built upon with the current universal hitstun in mind, which means no matter what I do, I have to make sure dgrav stays about the same or else risk making the characters more or less comboable. Hopefully once the new codes are out, this limitation can be overcome, and we can further experiment with character gravity settings without worrying about messing with their comboability. We will also be able to test new gravity settings for characters with gravity-dependent specials, so that will be nice as well.
Oh, and by the way, any changes in gravity will pretty much necessitate changes in momentum as well. The Falcon settings above result in noticeably less momentum.