1. TOS
2. Lower Decks
3. SNW
4. PIC
5. TAS
6. DS9
7. TNG
8. VOY
9. ENT
10. DSC
I've never watched Prodigy, which is why its not on there. TOS, Lower Decks and SNW first seasons are all legitimately good, and not "just" for a first season. PIC's first season is fine, and TAS isn't the most interesting series but the lack of outright horrible episodes puts it in its spot. TNG Season 1 would have beat DS9 S1 in general because I find DS9 S1 to be more forgettable, but the excellent DS9 episode Duet and the horrendous TNG Episode Code of Honor ended up deciding the ranking, even though I think TNG's first season is a bit more memorable in general. VOY Season 1 is just kind of there, mostly being bland and boring, with only Caretaker and maybe Learning Curve being episodes worth watching.
I went back and fourth on the bottom ranking, but I can find a half dozen episodes of ENT Season 1 that I would (and have) rewatched (Broken Bow, The Andorian Incident, Fortunate Son, Cold Front, Shadows of P'Jem and Shuttlepod One, fyi) while DSC's first half of Season 1 sucks, and the second half, while tolerable, has nothing I've felt like rewatching, so ENT gets to stay off the bottom of the list.