Re: Viable builds for ubers?
Well, I've tried this now. The mini-ubers were a total pushover; Izual cost me one full rejuv due to carelessness, but that was it. Lilith killed my Merc in one hit, but due to its poison immunity the Bonewall from Marrows lasted for something like 15 seconds against her. I accidentally had my ES staff in use instead of my Facet sword + Phoenix, but still Lilith died in maybe 20 Firewalls. Easiest Lilith kill ever.
The Ubers themselves were a different story, however. Well, I only fought Meph, but still. Without Revives it seems impossible. I didn't have full ES though (only 71%, although I had TK maxed ofc), and had statted all life, so I only had 1k mana and partial ES. If I statted all mana, maybe with good charms it could be done. I doubt it though, and I'm not gonna try it for now. I tried to take the Harmony bow off my Barb's merc and use Revives, but it required 119 dex and I only had 55. -.- I also forgot my Tgods to begin with and burned through all of my purples in one minute. Even when I did put it on, it made precious little difference. Meph spawned minions like crazy and I had no crowd control whatsoever. I could cast one Firewall, which he immediately moved out of, and then I had to panic-tp to safety.

So, the conlusion for now is that Sorc has no trouble killing mini-ubers, but the big fellas are a different story (at least Meph).
If I find some crazy rare worth 10 HRs, I may just make an Eternity and try this again. Maybe I'll respec and try full ES, too. But then Baal becomes the problem with his manaburn... Dream helm on merc might help against minions, to cast Confuse.
As a final comment, although the Bonewall and Lifetap from Marrows were essential in keeping me and the Merc alive, the repair costs were staggering enough to make Sorc ubering an unsustainable effort even under the best of circumstances; one Lifetap charge costs 14k to repair, and ~8 BW charges cost over 200k. There are always Orts (or was it Rals for armors?), but muling those would get tedious imo. This is a novelty build, and doesn't work even in that capacity atm.