I think if you're going to do crazy hard bosses you need to lose runbacks. In general I prefer easier boss plus runback, but first sinner was pretty great as a fight to encourage needle mastery. Also not anywhere near as overwhelming and nutty as many of the fights since there is only a max of 2 projectiles that move in straight lines on screen at once (blocks of needles that move together are just one projectile with a fancy hitbox in terms of cognitive load).

I served my time in runback hell (dark souls 2) I need not do them anymore. I don’t find it an enjoyable or rewarding gameplay loop just frustrating

The platforming and controls are so smooth that I actually enjoyed most runbacks. Bilewater can get fucked though.