This wad ignores much of what the SRB2 community at large considers "good", but ultimately proves that you don't have to be conventional to make a good levelpack. It uses its linear level design, forced character switching, and occasional time limits to provide highly focused challenges that force the player to adjust their approach. Despite how tight and deliberate this wad is, it never oversteps into kaizo territory; if you've mastered the vanilla campaign and are good enough with the 3 base characters, you can probably handle ASfAEe.
That said, not all levels here are winners; there's multiple of these weird open intermission levels that have a bunch of irrelevant stuff littered around a pathetically easy path to the goal. I'd think these are here for hidden emblems, but there are no collectible emblems in this wad (despite multiple intangible ones being scattered throughout the stages for whatever reason). Beyond those, there's multiple levels that feel too easy or too hard for their point in the game, or are just plain baffling (was Rerun Site really necessary?), and even levels I consider good suffer from oddities like arbitrarily excessive amount of rings and monitors. Specifically regarding Final Judgement, golden monitors exist for a reason. If you want to make sure the player has access to a specific power-up, put down one of them in a golden monitor, not 20 or so in regular monitors.
ASfAEe didn't blow me away, but it gave me a fair and unique challenge and made me consider if this community really has level design down to a science, or if it's just found its comfort zone.
I initially wanted to go back to map 1 and make it worthwile, but after three years of on and off working on it I kind off just wanted to close that chapter, so I made cutscenes to bait people into continuing instead. My brother asked me to help on a project, too, so I basically hurried off.
The frustration is partly intended. I know most people don't like that, but I wanted to add a fair bit of suffering to the mix.
I can't actually code in Lua or anything, so I wouldn't have known how to make a command to turn off ForceSkin in later playthroughs. I just wanted to make sure people would get a character that the stage is beatable with. Then again, a good bunch of the maps (after map 13) or so I stopped bothering to make them beatable on every character. I figured that if someone cared enough, they could just manually disable the ForceSkin via Slade, but that sounds like an unlikely thing to do now that I write it out loud.
I agree with pretty much all points you made, thanks for giving it a try!
I will keep it in mind for my next mod.
Or maybe I'll go back for version 1.3 in the future, now that I have recovered.