I would rather have Red Dead Redemption remastered, if only for an actual PC release, and to build up hype for the sequel which is apparently in development. That aside, I do get why people might want this to get a remaster; parts of the engine are really dated and chunky, and while the PC version is the definitive version of the game it still is plagued with these issues. It's not as bad as as VC and SA's ports, which had omissions and odd things missing when compared to the PS2 releases that the community is still restoring in 2015, but the fact IV can't even run at a constant 60fps on max, on modern machines, really says a lot on how it's busted.
I imagine the only way it'd get a remaster would be if it was for the games anniversary, the same way III, VC, and SA got updates for mobile phones. Rockstar seems like the company who needs an incentive, a kind of sincere point to update games, otherwise they don't really bother. You can see that between the world of quality difference between GTA V's enhanced edition and Sleeping Dogs' enhanced edition: the former somehow runs worse on greater hardware than its original version.