I had an original post with this info in it before but it was deleted in a forum cleanup -.- I'll repost my class suggestions. Feel free to discuss and offer more/better ideas.
===WOOD KING===
High Elven Swordmages who use a sword (short sword, long sword, dual-wield longsword, spellsword, dual-wield spellsword) and a handful of extra elemental skills which increase in number and power as they rank up. They serve as the primary melee DPS of the army though they don't necessarily have impressive armor.
Wood Elven Rangers who use a bow (short bow, long bow, crossbow, autocrossbow, flaming autocrossbow) and serve as a heavy ranged DPS at the cost of very little armor.
Dark Elven Assassins who use daggers (knife, dual knives, stiletto, dual stilettos, demon claw) which deal insane amounts of damage up to an instakill for every class regardless of armor at tier five. They also get a throwable knife which can stun. They have so little health and armor they will always die at one hit but gain a "life" every tier upgrade which when used up downgrades to the lower tier.
[PREMIUM] Draconian Sorcerers who uses an AoE staff (branch, sapling, oak staff, ash staff, dragon staff) and a variety of placed AoE traps (fairly hard to see) which increase in number and power as they rank up.
===UNDER KING===
Gnomish Engineers who use engineering tools (wrench, hammer, giant wrench, soldering iron, sledgehammer) and can interact with certain parts of the map to create traps, disable doors allowing access into other areas, and create pets. Their capability to do so increases as they rank up.
Goblin Alchemists who use no standard weapon but have a variety of potions, some to harm and some to help, which they can throw. The effectiveness and number of these potions increase as they rank up.
Dwarvish Prospectors who use mining tools (pick, hammer, shovel, makeshift pickaxe, giant pickaxe) and heavy armor to serve as the heavy-hitting primary DPS of the faction. They increase in armor, life, and damage very quickly as they rank up to make up for the fact they have no incredibly special feature. They can, however, steal resources from slain enemies.
[PREMIUM} Mechanical Golems who can both hit hard melee-wise and throw powerful chain lightning from their bodies at the expense of health. As they rank up their lightning attack becomes more powerful and less health-consuming. (spark, spark shower, ball lightning, arc lightning, chain lightning)