The classic games cap rings dropped at 32. I'd disagree that the game is "otherwise almost flawless", but the bosses are by far the biggest problem with the game. From OOZ1's "hey you stood in the wrong spot even though there was nothing to indicate there was a wrong spot, you're dead now" to FBZ2's "will flying into the bumper actually hit the boss, or will you simply pass through it and die to the spikes opposite? GUESS!" to CPZ2's "oh I know you wanted to play Sonic, but here, play Puyo Puyo instead!" the number of even acceptable bosses in Mania can be counted on one hand. The game would be improved by simply removing the bosses. And I'd go as far to say that's true of Sonic in general - while there are good bosses scattered throughout the classic games (most of S1, ARZ, HCZ1, ICZ2, MHZ1, and SSZ-K) most of them are just not fun and require you to either wait years for the boss opening to appear, or just rely on post-hit invulnerability to actually move on to some more gameplay. Why not do away with bosses entirely? They're just needless padding.