The GTA series just needs to fade away out of existance.
Their new approach to games is realism; have as much gritty realism and "realistic" acting car physics as possible (ignoring that you can take multiple shotgun and assault rifle shots to the face and shrug it off with a soda). The gritty realism approach, in my opinion, doesnt work for ANY game. But when it comes to GTA, which was always whacky and cartoony, I take it as a slap to the face.
Revisiting a pinicle is not a way of making your series better. Its a way of milking your audience. Re-visiting CJ wouldnt make the series get any better; they still have the opportunity to add and subtract whichever gameplay mechanics they feel like.
Remaking San Andreas or digging up a sequel would really feel forced at this point, CJs story was tightly woven. If the series has fallen (which it has), its best to let it fade out and go away. If it can redeem itself, good; but dont let it do so by climbing up a tree of nastalgia.