Older Characters in the game talk all about Hoenn. For Example, In Courmarine Town's hotel, an elder mentions a hot spring next to a Pokémon center, possibly referring to Lavaridge. And, in one town(I forgot) there's a man trying to sound hip and saying a phrase that makes no sense, possibly referring to the house of so-called "trendy people". The guy outside(in R/S/E) asks you what phrase is trending and then the whole family adopts it. (Mine was "Magikarp joking") And there are countless other hints!
Right now, we don't know if we'll get a Gen 3 remake. It would seem logical, as we have had Gen 1 remakes during Gen 3, and Gen 2 remakes during Gen 4. It seems about time that we get a Gen 3 remake. However, these hints don't necessarily mean anything, although I hope they do.