Well, Super Sonic is obviously more widely known, since he's appeared in almost all of the Sonic games, as well as in the animated series, whereas Hyper Sonic only appeared in one game, so Super Sonic is clearly the better choice. And Sonic's current Final Smash is already one of the best, so adding more abilities to it is just overdoing it.
Now, I do still want Hyper Sonic is appear once again, so the only hope left for a Brawl appearance would be this: I'm thinking that there can be an Easter Egg where if a Smash Ball were to appear while you're in super form (that is, if that's even possible), and you break and activate it while being Super Sonic, you'll transform into Hyper Sonic for 15 seconds (the same duration as Super Sonic). To make it fair, since it's just an Easter Egg, everything will be the same as if you were Super Sonic (except for appearance, of course), and when those 15 seconds are over, you convert back to good old, regular, blue Sonic.