I think Sonic could benefit from a variation of Smash Bros's DLC approach

[Scritch the Cat]

I've actually seen someone suggest this years ago, and while I wasn't really convinced of it back then, I think that was before Generations and definitely before Mania, so even functional mechanics were questionable at the time.  Also back then there was the sense that SEGA was making too much too fast, instead of going through dry spells during which what was going on with Sonic was totally hidden.  There's a fundamental difference between waiting half a decade for a new Mario or Zelda game and doing so for a Sonic game.  Namely, Sonic is on shaky ground conceptually; last we left off we had no clear idea what SEGA wanted Sonic to be and it seemed SEGA also had no idea what we wanted Sonic to be, and this, combined with how lackluster the games were, makes it highly questionable whether next game will be even worth the wait.  Devoting that much time and resources to an idea that might be a flop is a big risk.  So that's making me think SEGA should approach Sonic differently: Release smaller things for less money but more frequently, and DLC should be a vital part of that business model.

Here's how to start: Make or refine a good Sonic engine.  I would prefer something like 2D Sonic but in 3D, but that's negotiable; note though that this approach can also be used in completely 2D games.  Then release a short but solid game that uses that engine. 

Fans don't like it?  That sucks, but at least you didn't waste much time and money on making that thing that flopped, so get feedback and then make something else that is solid but more conceptually aligned with fan wishes. 

Fans liked it?  Great; now what you do is make paid DLC.  More levels, a challenge mode based on existing levels, hopefully more characters, even totally new stories can be added to the core game.

Of course this doesn't have to be the only thing SEGA does for Sonic.  But it's an approach that could finally solve their biggest problems, and fulfill their goal of keeping Sonic relevant.  Highly experimental game design is risky when it's big, slow, and expensive, but when it's small, fast, and cheap, it's a good way to test out ideas and find out which ones deserve more commitment. 

[Cosmos Rogue]

I think you're on to something, although I wouldn't want them to make a "small" game that serves as the basis for all of the DLC (although small games do seem to be the default for the series at this point). A big missed opportunity in my mind was that we didn't get more DLC for Generations and Mania, which were really perfect platforms for map packs. What we did get with Mania at least is DLC characters. With how many characters this series has accumulated you're never going to be able to include everyone's favorite character at launch, but if you take the approach of a fighting or hero based game, you could release a couple of new characters (and levels) every year to help keep the last big title alive and fresh during the interminable wait for the next big Sonic game.

[Wraith]

I don't know what this idea has to do with Smash Bros. You already get a massive and complete game out of the box with that,. The DLC just "more characters". Hardly a huge addition in comparison.

What you're suggesting sounds more like IOI's approach with the modern Hitman series, where they released bite sized levels first at a cheap price point to feel out how they wanted modern Hitman to be designed. Nowadays, the "World Of Assassination" is a huge game with over a dozen levels massive levels and 3 story arcs to explore, but it didn't start that way in 2016. For a long time it was small, incremental episode after small episode. People weren't very receptive to this episodic release structure either, since it made the act of just buying the game really confusing wrt what you actually get. Pricing was absurd with the cost of all content easily eclipsing that of a full price game, and it was hard to maintain interest in the game over an entire year of DLC.

When Hitman 2 came around they just finished 6 "episodes" and released them all at once as a full game. The game did a lot better when pitched as a full $60 product. Hitman 3 took a similar approach and it's doing even better than it's two predecessors, being the fastest selling games in the series.

The thing about single player DLC that most companies have begun to grapple with in recent years is that it doesn't do very well. Look at the trophy data for any single player game past the initial release and watch the numbers plummet. Most players just move on once they're done with a game, which is why you don't see expansions like The Last of Us: Left Behind or Undead Nightmare in their successors. Once episodic series like Life is Strange have even dropped the model entirely with newer entries.

Multiplayer DLC does a lot better, but I don't really know how Sonic could capitalize on that outside of spinoffs.

Your approach probably makes the most sense from the perspective of a Sonic fan like you or me that will spend hours and hours revisiting the games, but SEGA doesn't just make games for us. They have a huge audience of people that are going to play through the game once at launch and drop it that they unfortunately have to cater to. They're going to expect some content of significance or they're just not going to bite.

And to be blunt, as far as having room to experiment before they commit too hard for something. Sega should have game testers that they can rely on for this type of thing. They can target certain demographics and call more hardcore Sonic fans in to feel things out whenever they want. I'm not convinced that they're struggling to please fans and need our feedback. I'm convinced that they think what they've done is "good enough" to entertain younger audiences and they're content with that. Stopping and taking some time fine tuning the series mechanics doesn't seem worth it to them because the series is already doing good enough as is.

There's really nothing I can do for that mindset, so I just take my money elsewhere.