This is my opinion but i would love to see another wow movie but the Sonic movies are a good example of what was done right to break the video game movie curse, basically i think the mistake the first wow movie made was showing us too much at once, in reality it should have focused on specific characters a lot more and given more depth to them…that kind of thing.
Check out this link below about to do a video game movie right and think about it
I agree that the Warcraft movie squished in too much. Plus Stormwind should have been razed. Resulting in Lothar and other refugees fleeing north to Lorderon
Warcraft I was more one battle after another with a loose storyline. Warcraft II has a good plot but it was still too loose for a good movie. Warcraft III though had a very solid storyline that flowed well through each scenario.
Then there are the novels.
The first factor would be that significant knowledge of previous events would not be required. War Crimes would not be a good novel to movie choice.
One that I think would do well though is Arthas: Rise of the Lich King
Then there is War of the Ancients as three movies. But that is one that should be pursued after a few successful movies