This is a bit on the spoiler side but anyways.
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Tbh, I'm not entirely sure exactly what could happen. But the few things I'd like to have happened if something that more or less continued from the events of Rayman 3. If I'm getting it right, Andre get's turned back to a Black Lum at the end of the game (and judging that Rayman: Hoodlum's Revenge existed I assume he was). What I would have liked if Rayman 4 expanded from that point, but went back to a more darker tone akin to Rayman 2 or so, and to add to that, maybe Razorbeard could have been brought back and maybe have ending up teaming up with Andre as the main villains of the game. That way we could get a mix of what Rayman 2 and 3 had to offer and have a game based around the Hunchmen and the Black Lums/Hoodlums. And other characters like Ly and other R2 characters could have made a proper return to the series. That's something I always would have love to see happen, even if that seems like a pipe dream at the time of R3. Sadly, it seems that is the case.[/collapse]
I honestly don't hate the Origins/Legends story, but I just wish for something else. And with R1 aesthetics like Betilla and the classic level design and mooks here and there, I'd love to see more from the classic trilogy come back to the series, mainly some of my favorite characters and story depth that Rayman 2 does indeed have good about the series, imo.