Why not both?
Although that said gen 1 feels kind of overdone for me. If they were to do it again not only would I prefer a Yellow remake than another Red/Blue, but it would be great if they could make it more than just a Yellow remake. Throw in some other regions too. Johto would be an easy to justify addition, but what about Alola too? Give that some more time in the spotlight and also the new Yellow remake could not only give some nostalgia for gen 1 and the original anime season but it can also give some focus to the Alola anime too.
Bet Shiken that COD would outsell Battlefield in 2018. http://gamrconnect.vgchartz.com/post.php?id=8749702