Multiplayer was really thrilling for me as a fan of the more strategic side of the game. I have to give it to you guys that you managed to make a very thrilling, diverse singleplayer campaign, i don´t believe I made a flawless clear through a campaign even since Melvelous the first time. However, of course, once you clear them, you get to know what you are going to face, so you can ajust accordingly. Multiplayer offers variety of opponents and a multitude of strategy, so instead of ajusting to their strategy, you have to make a strategy flexible enough to fight around unknown factors. In fact, let me suggest something: In the last module of the single player campaign, have Melvin´s teams slightly randomized (Per stage, have a rooster of, lets say 5 characters, he uses 3 per game). That way, you´ll be better emulating the multiplayer experience against diverse opponents in the finale of the SP campaign, which sounds fitting
MP hasn't been bad but I really wish there was dungeoning coop. Far more fun for me. Love the campaign so far, great story.
2v2 would be cool too, just more added variety would really help. I guess the only problem is how much they can dilute the player population across different play modes.