First off, I know Tola is busy, so I don't expect anything to be changed overnight, but I also know he tends to be open to sound-boarding ideas for the server. Anyways here are my ideas for the Hell zone.
Rewards in Hell Mode from Quest Mobs: Basically variantions of existing items and gear to eliminate all potion use
-Full set of gear (similar to Abhorrents) with max armor factor: 3 Pieces - 33% Heal /use & 5 Pieces - 50% Pow/Endo Heal /use
-Elemental Procs: 25% proc of varying resist types (similar to quake proc) for example: Volcano (heat) & Hurricane (cold)
-Baal Weapons with slowest speed and max damage
Quest (since you can still unlock each act in nightmare zone, there instead needs to be an alternate Baal in the hell zone):
-Repeatable Quest to defeat Baal and his henchmen with a reward of 1 realm skill point each time completed.
-Encounter takes place at the Dragon spawn.
-The 4 Seals are in the middle with the following bosses on top of them: Andariel, Duriel, Mephisto, & Diablo
-Each boss has a special role: Andariel heals, Duriel debuffs, Mephisto casts spells, & Diablo does increased melee damage
-Each boss drops pieces of the armor set for hell zone.
-After you break all 4 seals Baal is summoned.
-Every minute Ball summons one of the 4 earlier bosses at random to assist him (up to a max of one of each).
-If Baal summons all 4 minions the encounter is reset with the seals deactivating and Baal disappearing.
-After you defeat Baal you are rewarded with random Baal Weapons and if your very lucky an elemental proc.
Anyways just my thoughts for making one hell of a final encounter for hell zone. After getting used to handling one beastly mob at a time (Diablo 3) I think this might be the next way to increase the challenge mode by making you have to deal with 1-4 boss mobs at any time.