Okay well I voted co-op because me and my friends would love to do the missions together. Something for the developers to keep in mind when working on the Multi-player is replayibility, you want to make something that can go on for hours and not get boring. as much as you could love a franchise or game after awhile most games get repetitive and boring when it comes to SP (although SF64 is long and fun every time) but MP is where a game can shine when it comes to replayibility. my suggestion is do everything that works well even if it sacrifices time, in the end you come out with a stronger game with alot more to offer. I’d say you focus on the co-op story giving the player options like ships/ characters with unique and different dialogue interactions in the story, different ways to approach bosses and missions that squad A.I can't perform. Then work on the simple online modes like team death match, than free for all, etc.
one mode that would be cool is a mode that could be called "star fox vs. star wolf". you could take that awesome model of the great fox that you guys have in the trailer, put two of them in the same map, mod one to be like black and red or something and have different decals to be the great wolf. The mode could be like Star Wars battlefront 2 or Battlefield 2142 where you have two capital ships and you have to destroy your enemies capital ship while defending your own. they can have hanger bays for health. Now you could have something like sector Z in star fox 64. Have the ship fly into a dark hanger and disappear, then the player could be given an option like "right click to use a turret" be it a main cannon or an anti aircraft and it wouldn't have to have ground gamplay inside the ship to get to a turret it would just be cycle through the turrets with your mouse wheel. it'd be just going from exterior of the ship to first person turret Something like this allows you to talk strategy with your team mates about who is going to do what for defense and offense. Objective based game play helps keep the game different and fun every time. For ground games you could have two bases with AA turrets and both teams are at each other to blow up the bases and win.
idk whatever happens I'm sure you all know what will make the game's multiplayer great