They have flight matching colors.
This is exactly what lore is, molded to fit the gameplay.Partially. That is still more gameplay than lore, since shadowmeld hasn't explicitly been a part of WoW lore. In WC3 its lore was specifically a blessing granted by Elune to her followers. Druids and male Night Elves like Demon Hunters did not have because at the time of WC3 lore they were not Elune's followers. Also it only activated at night, when the moon was out.
Shadowmeld hasn't actually gotten lore updates since the WC3 manual. It just exists in gameplay as a race-wide ability usable at any time. No lore explanation given, not even a simple update to say every Night Elf has it. It just exists as a gameplay that works for any Night Elf, including the Highborne Mages, during any time of day.
So WoW's Shadowmeld isn't actually lore based at all.
Pitlords are four-legged creatures. Eredar aren't original demons. I'd say Dreadlords, but they aren't original demon either. Perhaps, Su\inccubus?To be honest, Warlocks could have had more Pitlord and Eredar style forms to give more of an homage to WC3. Shadow Illidan was merely used because Illidan is cool. And it worked, cuz Warlock Metamorphosis was actually quite cool.
Really? You see them all as viable?Every Hero could literally be its own class in WoW. WoW is simply not flexible enough to ever get around to realizing them as new classes.