If you had to choose just one of those 3 things to MF, take Chaos Sanc.
Meph can't drop the highest TC's, so he's only really good to MF due to how easy he is to kill (moat trick, spam stuff); he can drop just enough valuable stuff that it's not a total waste of time. Pindle skin is much the same as Meph, except he has higher TC's. Still there's some TC's Pindle won't have (I think, it's been a while since I looked in ATMA). In both Meph & Pindle cases, you're only targeting 1 thing to do over and over and over; and a lot of MF'd items can be found just by clearing an area and stumbling into that GC that a normal enemy dropped.
Chaos Sanc has a high enough area level (and enemies inside good enough TC's) that they can really drop a lot of good stuff. Storm Casters have among the better rune drop rates. You should clear the whole area really, but even if you only do the seals & diablo, you're killing at least 3 super uniques and an Act Boss.
And it's also worth noting that if you only kill bosses, and don't clear areas, you won't really find that many potentially valuable socketed items. Bosses & Uniques, if they choose to drop equipment, won't drop anything less than magical -- it'd be a shame to miss out on a superior 15% ed ethereal 4os cryptic axe just cuz you were in too much of an anal hurry to kill Diablo quicker and skip clearing Chaos. --- Adramelk - 80 Druid @ Kilrogg;; Bleedthrough - 73 Shaman @ Kilrogg;; Casualty - 70 Priest @ Kilrogg;; Hashmal - 80 Death Knight @ Kilrogg
That said... you can find nearly every item from Diablo, although it doesn't seem like he can drop TC87. That means that the rarest sets and uniques can't be dropped by him (things like Death's Web, Astreon's Iron Ward, Tyrael's Might, Windforce and so on).
The only (set/unique) items that Pindleskin can't theoretically drop are Arachnid Mesh, Tyrael's Might, and Azurewrath, due to qlvl considerations (Pindle is level 86, and those three items are qlvl 87, so he can't drop them). Of those two, Mephisto can drop Arachnid Mesh and Azurewrath, but not Tyrael's Might because his TC isn't high enough... --- I know the answer... what was the question again? Visit http://d2offline.hostmine.us for legitimate offline Diablo II.
So what area should I add to the MF list? I'm trying to avoid Baal's place, since a solo sorc gets torn up there =/ --- TurnTurnTurn your brain in.~*ST*~ Now Playing: Etrian Odyssey 2, Diablo 2, Lunar: SSSC
Here is a list of the level 85 areas, where any item in the game can be found. Only the bosses/unqiues in these areas can drop EVERY item in the game. Act 1 - Pit Level 1 (Few Undead; Any Immunity; ~6 Boss Packs) Act 1 - Pit Level 2 (Few Undead; Any Immunity; ~2 Boss Packs) Act 1 - Mausoleum (Undead; ONLY Lightning Immunes; ~4 Boss Packs) Act 2 - Maggot Lair Level 3 Act 2 - Ancient Tunnels (Undead; NO Cold Immunes; ~6 Boss Packs) Act 3 - Sewers Level 2 Act 3 - Forgotten Temple (Upper Kurast) Act 3 - Ruined Fane (Kurast Causeway) Act 3 - Disused Reliquary (Kurast Causeway) Act 4 - River of Flame Act 4 - Chaos Sanctuary Act 5 - The Worldstone Keep Level 1 Act 5 - The Worldstone Keep Level 2 Act 5 - The Worldstone Keep Level 3 Act 5 - Throne of Destruction Act 5 - The Worldstone Chamber
From these, the easiest to run are the Pit, Mausoleum, and Ancient Tunnels. Of course, the drop percentages for the random bosses is not nearly as good as, say, Baal's drop rates, but if you factor in speed, then I think you don't do so bad. As a cold or cold/fire sorceress, the easiest is probably the Ancient Tunnels, with its lack of cold immunes. The Mausoleum usually doesn't have ranged attackers, if I recall correctly, so it's pretty straightforward so long as your mercenary isn't a wuss.