The only thing I can add is just a personal preference, but for an event like this, I'm all about the savory over the sweet. I'm a red wine drinker, and the idea of noshing on cookies and cake makes my teeth bleed.
Not sure how mainstream this is.
Same here. Particularly as a mostly vegetarian (I'll eat fish but only from a few sources), it can be a bit much to munch on a lot of cookies and fruit.
My requirements are plenty of seating, a variety of good food, fun music that isn't blaring so that there are places where people can have a conversation without shouting. If it's outside during the warm months, a shady area is great. Also, clean bathrooms. I've been to way too many events where there's only two stalls for 150 people for an evening and the toilet paper runs out by the end of hour one and by the end of hour two I'm afraid to touch even the door.