If you could change anything about Ben 10, what would it be?
Except for Gwen...and well, the show is about Ben...so....
bring back all the original series voice actors
1. Fix all the plot holes between OS and OV.
2. Use the OS/AF/UA Art Style.
3. Make UA better.
4. Make more use of the actual concept of Ultimate Forms.
I agree with number 3.
For one thing in OV they should have have kept the same animation style of AF and UA. Secondly, I would remove all of the stupid bad guys like Nhancy Chan, The Incurseans (I thought that they were a little bit corny) , amd Dr. Psychobos. And Third, couldn't they have put in the better villains in more often like Vilgax, The Forever Knights, Eon, . Fourth, they should have explained how Ben lost the Omnitrix in the time period between 11yr. old Ben of OV and 15yr. old Ben of AF. And Fourth, they should have kept Gwen and Kevin on the show as regular characters and added Rook instead of sending Gwen to stupid college and having Kevin be her little tag-along for the trip. Finnaly , they should have made it so that the Omnitrix could still let Ben go Ultimate but now with more forms.
Eh...I have to disagree with one, two and the last one. Also, you said fourth twice.
Ultimates were a bad idea...oh yeah, i've got ultimate forms, so...what's the point for the other aliens if he is always going to use the ultimates? you know...they are the most powerful and everything. I like using the aliens as a challenge, when he get's the wrong alien...i like that...when he was ultimate he could easily win any battle...even with Vilgax. Also....GWEN MUST GO TO COLLEGE! I mean...SHE'S GWEN!
I love most of OV but if there's one thing
1. Make sure that NRG's suit doesn't have the trix, but his true form does
2. maybe having albedo be a hobo who carries a slightly broken ultimatrix (basically albedo would only have access to the original 9 along with canonbolt and they all are stuck in ultimate) and teaming up with psycobos to create a Mega nemetrix Ultimatrix combo (Imagine having combinations of the predators and prey, like a Slamdrillo)
3. Ben's alien forms would start to slowly turn back into ben, so that it really feels like he changes species instead of a little flash
4. the Forever knights would be more underground and advanced, but still otherwise silly
5. The Prototype omnitrix would look like it was a little more "malware'd" (Red streak marks across the trix)
6. Ben would fight albedo a little bit kinda like how he did in OV, but at the end after shooting Ultimate SpiderShark he'd make the badge of both trixes touch and start to meld together before azmuth presses the ultimatrix and than Albedo turns into a kid (because seriously, when else did the omnitrix and ultimatrix show that they can control the age of the user)