Classic 2D Sonic doesn't need a S4E3. It doesn't need a Sonic 5.
It needs a completely new branch, where sequels get a 2 and 3 and so on all over again (assuming sequels to this are ever made) to both distance itself from the critical trainwrecks S4E1/E2 were, as well as to manage expectations as to how much it takes from the classics.
This is what Sonic Advance did with its modern aesthetic. And it was reasonably successful in its own right. I don't see why something similar can't happen where a new series brands itself to be first and foremost a throwback to what was good about the classic games.
And as much as I am anti "fans do what SEGA don't" (which is a really stupid mindset, really*) the fact that the Taxman CD/1/2, various fangames (LakeFeperd's stuff might be the most prominent but there's so much out there) and Freedom Planet exist in the past few years is pretty telling, in that those got a lot about the classics right but didn't claim to be a continuation of classic Sonic. The complete antithesis of Sonic 4 which claimed to be a continuation of classic Sonic, but didn't get much right at all.
*edit: As clarification, this is stupid because more often than not it's used to put blatantly sub-par fan work up on a pedestal while bashing anything and everything SEGA, with little to no understanding of how game dev actually functions both technically and as a business. A sad showcase of double standards, really.
This post has been edited by Falk: 05 January 2015 - 08:51 AM