[Stroker Ace]

1. Have Progression, Abilites and Spells from Faction and Trade Skills

Having progression just through leveling and gear kind of limits uniqueness of player characters. The more avenues you have to make your character different, the better in my opinion. Kind of like how WoW has race specific buffs, but do it on a broader scale. It might even be a good idea to give bonuses and abilities to every single race/class combination, kind of like Priests in WoW (and like the canceled Hero classes).

Examples:
Blacksmithing:
-Make Weapons and Armor
-Adds +Strength, +Stamina and +% max melee damage based on trade skill level
-Create armor, weapons and trinkets with unique, one of a kind abilities
-Abilities:
Trade Skill Level 50: Vicious Strike (Melee) - A devastating blow that deals normal damage, but leaves the target writhing in pain for 3 seconds (1 Min cool down)

Trade Skill Level 100: Heat Renitence (Passive) - Raises your maximum Fire Resistance by 10%

Trade Skill Level 150: Scorch (Magic) - A level scaling fire based nuke the leaves the target aflame for a short period of time (15 Sec cool down)

Trade Skill Level 200: Weapon Toss (Range) - Allows you to throw your 1 handed weapon to deal up to 75% of your max melee damage

Faction:
Random Evil Caster Faction:
-Items and Trade skill specific patterns (Like Aldor/Scryer)
-Your Melee/Spell/Ranged abilities deal additional shadow damage on top of their normal damage, based on your faction level.
-Holy and Light Spells Deal 5% more damage to you as they normally would.
-Abilities:
Blah Blah Blah

I'm sure you get the point.


2. Item and Gear Generation and Item Diversity

One thing I hate about most MMO's is the lack of stats and unique abilities on items. One of the games that had item generation correct was Diablo 2. The items had random stats, charges of certain abilities, magic find, auras, life and mana steal, summons, sockets, chance on hit/struck/kill/death/level up, scaling stats by character level, + to skills, damage shields, percentage based stat increases and so much more crap. They even had items with spells and abilities you couldn’t get from any class, unique to that item. The only issue with having a item system like this is building encounters around it. Which is a whole different discussion, and probably the most cumbersome job to do with making a MMO.