I've not used Vanced for a while so I'm not up to date with it's features, but..
Return dislike button - not sure what you mean? The dislike button works fine on YT, can press it then press it again to cancel the dislike no problems, if that's what you meant?
Resolution - I have it set to high quality and it always plays videos in at least 1080p. If I want it higher I can just select whatever resolution I want when the video plays, no issues.
Why is Shorts button unneeded? Shorts on YT are great watch them all the time, it's nice to have a button to go straight into it.
Tap on seek bar - as opposed to having to drag it? I would argue the opposite, dragging is better as can then select a specific time, instead of tapping which is guesswork.
Sponsor block - So Vanced will auto skip any sponsor stuff in a video? Is that only if it has 'Includes Promotion' thing showing? As a lot of videos don't have that and they still show sponsors.
With YT I can watch a video on my phone pause it, resume the same video at the same spot on my tablet, pause again, then resume at the same spot on my TV. Can I do that with Vanced?