I wouldn't mind revisiting VC or SA, because it'll be completely different from the last gen consoles. It'll be incredibly lifelike, and would look amazing, VC in particular. However, all new locations have to be a priority, it gets tedious with the same 3 places over and over again. Point 5 is perfectly okay, hopefully it won't hamper the experience too much, point 4 would be good for uploading to the net, depends how long the replays will be, 3 is slightly worrying, that'll surely be fixed or at least brought up to 40 FPS, and an unfinished ending - hopefully not, ending a game on a cliffhanger sucks IMO.
EDIT: Almost forgot point 1, there's always been satire in the GTA series, and this will definitely continue. I don't think it'll be a fully blown thing though, it might just be some small references every now and again.