Sonic Classic Heroes.That gives me a different idea.
Well you have a ton of features and customizable stuff in it.
For example, you can choose to either play only Sonic 1, Sonic 2 or both games combined in one playthrough... WITH SRAM saving.
Second, you get to choose which characters to play as. You can choose between Team Sonic, or a playthrough with Team Chaotix. I believe you can even choose if you want Sonic alone, or with Tails, or all 3 (Sonic, Tails & Knuckles). You can swap between any of the 3 characters from a particular team at any given time during a playthrough.
You get Super and Hyper transformations (depending on whether you choose to play both Sonic 1&2 together).
And a ton more. Bugfixes from both Sonic 1 and Sonic 2 are implemented as well.
I even replaced my Sonic 1 and Sonic 2 ROMs in my SD to Sonic Classic Heroes.
It's that good.
What if somebody hacked Chaotix and removed the stupid fucking tether system and/or redesigned the levels to be less mundane. Sonic Ed 2 supports editing Chaotix level layouts as well as enemy/item placement so it'd be easy to do for someone skilled in Sonic level design.