Holy shit you could not have any worse of a take about Mania. Mania easily has some of the best level design in the entire franchise, it's better than Sonic 1 & 2 for sure in that aspect. Nobody had a honeymoon period with that game, it's still regarded as a great game and the only complaint the game ever got since it's launch was the fact that it's mostly old stages. But the level design is so different and original it's easy to forgive for that.
I swear GAF legit has some of the dumbest takes I've ever seen on Sonic games, another user here saying the Frontiers cyberspace levels being worse than the Forces ones is LOL-worthy. Forces was dull as fuck all around and the level design in Frontiers at least has non-linearity even if there's heavy asset reuse.
Nobody is praising Frontiers because it's a Sonic game, if anything it sounds like the users here are bashing the game because it's a Sonic game lmfao. The game is very fun and does actually accomplish it's vision in an enjoyable way, it's just that the game is jank as hell. And tbh jank isn't always a bad thing, the game could have used more polish but it's very enjoyable so far, if you go outside of this website you'll find that to be the consensus. I'm having more fun with it than 90% of AAA shit nowadays, and ultimately fun matters more than anything else with a game.
Werehog was only really crap on Wii/PS2. Imo on 360/PS3 the Werehog hate is kind of silly, it's a perfectly ok, borderline fun style God of War rip-off that got pretty unfairly shat on because you didn't go fast in it. If you take that aside and just play it for what it is, and not what it wasn't, it's fine. It's significantly better than the absolutely dogshit emerald hunting stages and Tails's mech stages in SA2.
Also, side note, Frontiers is currently sitting at 95% Overwhelmingly Positive out of nearly 6,000 reviews on Steam, so the notion that critic scores matter at all with games like these still remains doubtful.
An 8/10 is perfect for Frontiers imo. It's good, borderline great, but not perfect.