You should increase azgalor's size.It is difficult to take him as a serious enemy while the doomguards and infernals are taller.
I believe you should change the names of the races.
For example:
1) Protectors: sentinels , druids , kirin tor , silver hand
2) Corruptors: Dark horde , Fel horde , Dreadlord insurgents , Lich king's servants.
Also if you can seperate each unit to the faction that fits the most.
For example:
Sentinels: archer , huntres , dryad , hyprogryph rider , night elf catapult , faerie dragons ,( and if you can add the night elf messenger model and give her healing abilities , the sentinels will have some kind of a priest.)
Druids: druid of the claw , druid of the talon , chimaeras , mountain giant , and some furbolgs.
Silver hand: footman , archer , knight , priest , grypthon , dwarf units ( dwarf canoneer , helicopter , dwarf tank).
Kirin tor: swordman , battle mage , fire mage , sosceres , dragonhank , arcane golem and final unit phoenix.
Dark horde : grunt ( the new model) , spearthrower , rider , wyvern , black drake , kodo , dark shaman( abilities: curse , fel heal ( normal healing with different icon) and spell shield) , catapult , ogre brute , ogre magi.
Fel horde: fel grunt , fel rider , warlock , fel kodo , red drake , nether drake , doomguard , catapult ( no chaos attacks).
Dreadlord insurgents: ghoul , abomination , necromancer , gargolye , giant skeleton ( and archer) , meat vagon.
Lich king's servants: ghoul , abomination , banshee , nerubian mage , frost wyrm , oblivian statue ( and destroyer) , crypt fiend.
HEROES:
Sentinels: priestess , warden , demon hunter , dryad comander.
Druids: keeper of the grove , first druid ( malfurion with different abilities) , a furbolg hero , mountain protector ( mountain giant biger in size than the usual ones with different abilities)
Silver hand: paladin , mountain king , archer comander , grypthon master
Kirin tor: arch mage , blood mage , phoenix rider , elven comander
Dark horde: blademaster , ogre leader , ogre mage comander.
Fel horde: axemaster( grom hellscream model with different abilities) , warlock( Gul'dan or Drak'thul model) , orc death knight.
Dreadlord insurgents: dreadlord , pit lord , doom guard comander( no chaos attack and some good demon abilities) , eredar lord ( no chaos attack and some demon abilities).
Lich king's servants: death knight , lich , cryptlord , banshee quin.
Now i know that i have some lacks of information about my ideas, but if you truly like them ( which will be a great honor to me since you know: yeaaaaaaah me ideas are on a map) you can find many ideas here on hive or dota or ask me again( perhaps i will think of something).