It's hard being a Sonic Rush Adventure lover because it does make a lot of great improvements and I prefer the level themes, and the difficulty curve feels a bit more forgiving than the original...but much like Sonic Rush the way it uses both screens has all but guaranteed it'll never get ported to anything ever
I also in general kind of suspect Sega is kind of trying to distance themselves from Dimps after they kind of struck out with Sonic 4 and Lost World 3DS so