Since the next mainline game won't be out Gill 2017 Sega should totally make a new Sonic collection game for this year's 25th Anniversary. But instead of emulation they should focus more on ports:
Taxman's Sonic 1, 2 & CD releases as well have redo Sonic 3 & Knuckles
Port Sonic Heroes as a HD re-release as well as include the HD re-releases of Sonic Adventure 1&2
Emulate Knuckles Chaotix, it'll be the first time since it's initial release in 95
Port the Saturn/PC version of Sonic 3D Blast which hasn't seen the light of day since their original releases despite being the better versions.
HD remaster of Sonic Colors and have that appear for the first time on Sony & Microsoft Consoles.
Then they can throw in the usual suspects lime the spin-off games like Sonic the Fighters, Sonic Spinball etc. but use the most modern ports of those games. It'll also be cool to throw in some Sega history as well like Virtua Fighter, Outrun, Enternal Champions as well.
They could do it similarly to Rare Replay with in game achievements unlocking behind the scenes type stuff.
For 3DS they could port all of the handheld titles since most of them already natively on the 3DS as well as port Sonic Pocket Adventure, Sonic Advance Games, Sonic DS Games and the Sega 3D Classics version of Sonic 1&2.
Taxman's Sonic 1, 2 & CD releases as well have redo Sonic 3 & Knuckles
Port Sonic Heroes as a HD re-release as well as include the HD re-releases of Sonic Adventure 1&2
Emulate Knuckles Chaotix, it'll be the first time since it's initial release in 95
Port the Saturn/PC version of Sonic 3D Blast which hasn't seen the light of day since their original releases despite being the better versions.
HD remaster of Sonic Colors and have that appear for the first time on Sony & Microsoft Consoles.
Then they can throw in the usual suspects lime the spin-off games like Sonic the Fighters, Sonic Spinball etc. but use the most modern ports of those games. It'll also be cool to throw in some Sega history as well like Virtua Fighter, Outrun, Enternal Champions as well.
They could do it similarly to Rare Replay with in game achievements unlocking behind the scenes type stuff.
For 3DS they could port all of the handheld titles since most of them already natively on the 3DS as well as port Sonic Pocket Adventure, Sonic Advance Games, Sonic DS Games and the Sega 3D Classics version of Sonic 1&2.