Call me crazy, but I would much prefer FFX HD over FFVII remake, for a number of reasons.
1) An FFVII remake is extremely risky and expensive. When was the last time you tried playing FFVII? If it was recently, you'll notice that it
isn't that great (*gasp*). It has not aged well at all. An FFVII remake would require extensive gameplay changes to bring it up to "modern RPG standards", whatever that means. Unfortunately, if you change anything, purists will cry foul and hate on the game for having any changes at all, even if they're unequivocal improvements. It's lose-lose.
2) FFX HD on the other hand is cheaper and easier. There are no
HD remakes of PS1 games because they would require extensive (and expensive) redrawing of graphics assets. HD up-rezzing is relatively cheap, by comparison, especially with the PS2's impressive graphics, so there's less of a leap. Thus, you'd get a portable version of one of the greatest JRPGs of all time.
3) FFX HD would most likely be based on FFX International. This version of the game included a bunch of bug fixes as well as a huge endgame sidequest involving the Dark Aeons. International wasn't even the final build to the game, either. FFX EU came out so late that it also had all the International bonuses. Thus, there's no reason for the FFX HD remake to be based on the vanilla FFX release. At worst, the International content would be locked behind DLC but that feels out of character, since no other HD remake has DLC.
4) FFX > FFVII, u mad bro?