I saw your thread on the Game Dev.
Honestly, you should do which ever you like, it's not up to the audience what you make, just like it's not up to you what Nintendo make next.
But in all fairness, there's already someone doing a Yellow Remake.
and i believe a Red remake was released somewhere around on Youtube.
So, you best bet is Blue/Green.
Blue would be better, since nintendo did not remake it.
Anyway which ever you do, I look forward to seeing it.