I'm having very mixed feelings with this game. When it works it's amazing, but those moments usually don't last long and the game soon reminds you that this is ultimately a (very good) fan game. My main complaints are pixel-perfect collision detection with crushing obstacles, the time limit which frontally oposes the exploration component of the game and having to restart the levels from the first act when you lose all lives. This last one is making me drop the game in frustration often and making it harder to pick up every time. It´s not funny spending 20 minutes in a level exploring everything, then dying stupidly due to a bottomless pit, crush obstacle impossible to see on time or boss attack you didn´t decypher yet and having to repeat everything again. And yeah, the game´s not hard, but I like exploring and trying things and that often leads to me losing all rings or a life. With a penalty so big for losing all lives the game seems to push you away from exploring, but if you just rush through the levels they become boring.
I´ll give it some more chances, but with all the awesome games coming out on Switch I´m running out of reasons to drop other games in favor of this one...
Hm. The time limit is far more generous, or rather less of a problem, than in Sonic 3 and Knuckles, for sure, at least it feels that way. Don't forget that while you are probably meant to explore (by repeatedly playing the game), you aren't meant to spend all day exploring in one go. They give you just enough time to look about and go different ways, even backtrack here and there, then finish the stage.
Don't forget the game gives you quite a few save files.
As for losing all your lives, that might be something to philosophize about with modern games.. do games needs lives? How much of a set back should failure be?.. But everything about this is a love letter to classic gaming, specifically Sonic games. In Sonic 2, when you lose all your lives, you start the entire game over. Think about that for a second. Personally, I think having set backs like that are good. It encourages a 'stopping point'. I just spend 30 - 45 minutes playing Sega Genesis.. oops, but I died just before the last level! Noooo.... Oh well, I'll wrap up the controller and play again tomorrow.
Because this game saves your progress at each Zone, even if you die in act 2, you can realistically recover your progress in another few short minutes. That, and it's pretty generous with rings and lives in general.
Well good luck. I agree with you about mixed feelings on the feel of the game, the overly sensitive crushy deaths, the recycled fan feel, but it's still great, and I'm still playing it.