Ok so far there are 5 different races right?
Maybe you can re create this race thing!
You pick race at start before host start game, each one start with custom building for that group of races, then you upgrade it into 3 different races set up that way to provide 1 tank, 1 support and 1 killing race! With cool combinations and 3 players you will be able to use those 3 combining humans (humans), humans (Dwarfs) and elves (forest spirits) for example 
This will create new unique race system that will be different from everything seen so far!
Players will be able to use large number of combinations, with new custom hero system that will be explained in another thread this map will rule and once for all crush all other footman maps!
let me now present my vision of awesome race system that can be easily edited, changed or upgraded 
Human:
Human (Fighters)
Peasant -> Militia -> Footman -> Knight -> Holy Knight -> Red Dragon
Abilities:
-Increased Armor
-Armor Aura
-Chance to block damage
Dwarf (Hunters)
Peasant -> Rifleman -> Mortar -> Siege Tank -> Gyrocopter -> Griffon Rider
Abilities:
-Headshot
-Splash Attack
-Barrage
Blood Elf (Magic)
Peasant -> Swordsman -> Blood Elf Lieutenant -> Priest -> Spell Breaker -> Hawk Rider
Abilities:
-Feedback
-Magic Resistance
-Magic Attack Night Elfs:
Night Elf (Hunters)
Wisp -> Archer -> Huntress -> Dryad -> Hippogryph Rider -> Chimera
Abilities:
-Critical Strike
-Increased Range
-Increased Attack Speed
Ancients (Fighters)
Wisp -> Treant -> Ancient Protector -> Ancient of War -> Ancient of Wonders -> Green Dragon
Abilities:
-Improved Regeneration
-Cleaving Attack
-Entangling Root
Forest Spirits (Magic)
Wisp -> Spirit of Vengeance -> Avatar of Vengeance -> Wrath -> Spirit Owl -> Faerie Dragon
Abilities:
-Evasion
-Possession
-Phase Shift Orc:
Orc (Fighters)
Peon -> Grunt -> Wolf Rider -> Shaman -> Kodo Beast -> Wind Rider
Abilities:
-Increased hit points
-Increased damage
-Damage Aura
Tauren (Magic)
Peon -> Wolf -> Tauren -> Spirit Walker -> Eternal Spirit Walker -> Black Dragon
Abilities:
-Healing Wave
-Life Regeneration Aura
-War Stomp (Chance to deal damage to nearby enemy units)
Trolls (Hunters)
Peon -> Troll Headhunter -> Troll Berserker -> Witch Doctor -> Warlock -> Troll Batrider
Abilities:
-Poison Attack
-Berserk
-Attack Speed Aura Undead:
Undead (Fighters)
Skeleton Warrior -> Zombie -> Ghoul -> Abomination -> Infernal -> Frost Wyrm
Abilities:
-Disease Cloud Aura
-Unholy Attack (lifesteal)
-Lifesteal Aura
Crypt Warriors (Hunters)
Skeleton Warrior -> Crypt Fiend -> Neruabian Warrior -> Nerubian Champion -> Nerubian Lord -> Gargoyle
Abilities:
-Cold Attack
-Slow Movement Speed Aura
-Spiked Skin (return % melee damage back to source)
Revenants (Magic)
Skeleton Warrior -> Skeleton Mage -> Necromancer -> Revenant of Death -> Voidwalker -> Nether Dragon
Abilities:
-Rise Dead
-Armor Reduction Aura
-Armor Reduction Attack "Abilities"
1 ability from above should be added to first unit for each race (level it with unit levels)
1 ability (I suggest aura) should be added to 3th unit for each race (level it with levels after that)
last ability should be added to 5th and last unit for each race (I suggest special attack)
Or you can add all those abilities to each unit in custom race and level it with improved base!
i really hope this idea gets accepted.