Ripley 8 never should have been, even Alien Resurrection's own narrative makes that clear, to their credit it's not treated as the same person and nobody has continued from or imitated it (Original Sin being the one oddity) for damn good reason.
Sean Fifield never actually died though, he just changed essentially, that's the intention as corroborated by the behind the scenes. Him and Doctor Charlie Holloway, and the Engineer head, and the "holocaust painting" all the same shit.
I think there was a good story to be told on LV-223 with the characters you refer to, but we got Prometheus, for better or worse.
As for "SiL like" we have The Perfected.