The other thing I'd do is go back and do a series that actually tells the story from the beginning (meaning starting at Sonic 1), including adapting the games. Then you can throw in all the things I described above into that. Like maybe just before the issues start adapting the Death Egg Saga, you can do an arc that basically covers the events of SatAM and Adventures. Shortly before Adventure, maybe do a single issue about Sleet and Dingo and maybe Bartleby, in an adventure that's as much like Underground as would make sense in the games' universe. After that, do a few issues about some of the spinoff games that fit into that part of the timeline (so say Pocket Adventure or something), then before the Adventure adaptation, do an issue or two that adapt the beginning of Sonic X, again fitting it into the games' universe. Key to adapting the episodic things like this is using montages to establish that many adventures happened which you don't necessarily show on the page. Instead, you just show one panel each representing a few key memorable moments. The same thing could be used again later for an issue or two that adapt Sonic Boom. After Sonic Adventure 2 or whatever the last game Sonic X adapted was, you can do an arc adapting the final season that never aired in Japan (and I never watched), or just make reference to it happening and don't even show it (outside of maybe a montage or something, as I mentioned), since as far as I know, that season would fit very well in this universe in the first place, and is already in a story-focused medium, so it doesn't really need to be adapted at all. Basically, just tell the stories of all the games in order, and try to slot in adaptations of adaptations where they would logically fit. There's enough material to adapt to keep a series like this going for many years. Also, a brief adaptation of the movie (but again altered to take place in the games universe) would happen, but it would be a flashback, because beginning the series like that would suck.
Alternatively, just do something like this for the "Classic" games, since Adventure is already story-heavy and you can just say to look at the game for the full story. Maybe the series stops there, or skips over the games that already show their stories with dialogue heavy cutscenes (meaning it just skips to adapting spinoffs like Advance, or Mania, but maybe people would want to see the Adventure adaptation by that point). But for the rest of the games from the '90s, people miss out on the story because most of the story was told through the manuals, never localized, or shown subtly through background details. Those could benefit from comic adaptations that actually tried to be faithful to the source material. Many were adapted before, but never close to faithfully. And again, you could fit adaptations of adaptations in here, to establish how those characters and concepts could fit in this world and thus be used in future stories.
This is all assuming that a series that takes place in "the present," meaning after the most recent game, continues. That series would then have access to any characters from adaptations that were included in the "past" series. Instead of doing spinoff series to focus on OCs, do spinoff series to fleshing out parts of the world and history that are already part of the Sonic series, but which you wouldn't otherwise expect the kids reading the comics to be familiar with. Instead of telling them to read a bunch of fan-translated Japanese manuals and watch a bunch of old shows, you can adapt it into the comic universe they're already reading.
And if all this sounds autistic, it's comic books. Comics always do this type of thing, mashing different continuities together. Just look at how they do it, and do it here. Note that it does not need to be nearly as autistic as they make it, because they're trying to keep 90 years of material and reboots all being equally canon. This would only be taking 30 years of material, and there would be a strict sense that the games' material is always top priority.