You're building a "custom content" server...

[Morningbreath]

Just to narrow the focus of the discussion to something somewhat feasible for an unpaid dev team, pick the choice below that you would MOST want to play in. The main goal is to preserve the overall gameplay style of classic Everquest but with some new things added to the mix.

-Class revisions/spell changes

-New zones

-Mob AI/behavior

-New Quests

-New Loot/item effects

-Tradeskills

If it was me I'd go with Class revisions/spell changes.

-Wizard damage spells would be reworked from the ground up with some ability cues from the enchanter and rogue.
-Warriors would have a temporary self-haste ability as well as a broader array of combat skills
-Druids get Spirit of Cobra, a strength-based-on-level poison DD proc buff
-Rangers would have access to a completely viable Archery ability at all levels, some spells transferred to magic arrow effects
-Mages could summon a healing pet(gasp!!)--moderate heals of course nothing close to CH
-Clerics would have self-ports to most dungeons
-Bards would have Bind Affinity
-Rogues would have trainable access to all playable race illusions/faction adjust
-Necros could reanimate fallen players temporarily
-Shaman could bestow Spirit Walk on fallen players
-Monks would be able to craft self-only bandages and pull from longer range
-Shadowknights would have a much better and lower level Life Tap proc buff
-Paladin would have a Increase Healing Effect self-buff
-Enchanter slow would be changed to Spell Slow ONLY, with higher percentage returns starting at lower levels