Dark Prince:

"I would be interested to know the other players who agree that long games show the greatest skill. I think they show the least skill."

I don't think the length of the game is too important. I like to see a player create an imbalance (e.g. Recon vs 2 or 2 vs Redon, 4 vs 5 or 5 vs 4, etc.) and then demonstrate they know how to play it advantageously.