Are you charging $25-30/head or planning that as your target food cost? As others here have said, maybe talk to the folks about a theme-this will narrow down where you're going with the food. If targeting $25-30pp Mexican fiesta theme would fit the food bill ;).
Station it out, cold with salsas, ceviches, etc..here. A hot manned station doing asada, fajitas, etc, over there. Hot chafing line with beans, rice, enchiladas, etc somewhere else.
If $25-30 is your food cost then Kuan's Grand Buffet is great. Seafood station with shrimp, crab claws, oysters, etc...Carving station with a steamship(inexpensive but big, alot of oven space) or roast prime rib. People of that generation are typically fond of rack of lamb. Selection of salads and so on.
On to facilities and staff. Do you have kithcen to work out of? Will you be renting ovens, hot boxes, reefers etc. Are you prepping elswhere and transporting? You need staff to pass hors d oeuvres(if applicable), buss, man stations(if applicable), run food, man the kitchen etc....One person-you-won't be enough to run smoothly. Will Client provide your staff also or do you need to.
Sorry if you've the logistics all worked out already and I'm just rambling. No offense intended here just things that pop up to me.