Honestly, if any character deserves to die not in another parallel universe, possibly in the 50s, and never came back to life. Everyone forgot about him including the bear would be Archie.
The writers get their heroic ending. The hero, in their eyes, is dead. The other characters rejoice because he is the worst, and they must keep making him feel good afraid to bruise his ego. Now they can drop the act breathe, and get back to normal, for Archiekins is dead.
The girls are happy because whatever potion he bought from Cheryl to be the Stepford wives around him is broken, but Cheryl will say it was her Momsy.
Uncle Frank, god, he can die too. I don't count him as a main, though. If anything, it will be Midge dying in childbirth from having Fangs baby, so Toni and Fangs decide to raise it.
I'd say let it be Alice and Archie, either one, but knowing these writers, we can't bet on that.
I'd say Jughead he'd always sacrifice himself for his friends, but you know what? He deserves to live to thrive, and he's done it enough, but if he needs to, he will, and he'll be okay with never coming back, no matter the time frame. However, if he finally finds love and it works, and they kill him or his lover, that's just cruel. Would the writers do this to Jughead? Absolutely.