Originally Posted by
Pakheth
Did you play the Warcraft games? They were more colourful than most other RPG/RTSs at the time, much more than for example Diablo. Not so many grungy earth tones but instead bright reds and greens. The armor is simple in design, but bulky and large, and the character designs are overdimensioned, simplified, quite cartoony. It started in the RTSes and continued into WoW.
And yes, the concept art was edgy but that wasn't what we ended up with inside the games. Look at Diablo to see how the different styles differ. They are much more edgy and dark. And yeah, the Pandaren was originally much more ferocious and Japanese inspired with samurai weapons and clothing. It's a shame we did not get to see so much of that, but I can imagine Blizz did not want to mix it it too much. We did get the ShadoPan at least.
You also have to remember that Blizzard took a lot of inspiration from the Warhammer universe and they too had a stylised style at the time with bulky overdimensioned armor(still do, especially in 40K) and plenty of colour. Not everything was Chaos.