Let me quote someone here - it might sound familiar:
"Nothing beats the real thing" (TM)
If that fails you can still try to write or port a decent mgd (genesis) emulator and play the next best thing to the real thing...
The worst that you can do is imitate. The Sonic Team spent many man-years making the gameplay right.
Any good Amiga programmer should be able to do a Sonic like engine within a few weeks, months at most. Getting the gameplay right would be a few years more
Another point is innovation.
Amiga was the synonym for innovation in its heyday.
With a project where there are no financial, deadline or management constraints you should be able to do the absolute best game that ever graced the Amiga scene. Instead you copycat an existing one.
Please do the miggy a favor and create your dream game instead - I am sure everyone has one, I know I do (just not the money to make it happen).