People with more than one monitor has to wait when they start the game, for the "Device Selection" panel to pop up. (https://imgur.com/a/k4DEJ)
What i suggest is, to give the option to set a prefered monitor and resolution in the panel, so you don't have to choose everytime you open the game. Personaly i feel like the waiting is quite long for the little box to pop up, and i've also talked to other mates with dual monitors having the same problems.
The reason i think this would be good is because it would make it much quicker for dual monitor players to launch the game.