If it's not formal and I really don't feel like stressing, I'm all about assemble-your-own fajitas.
For apps, put out good chips with a black bean & corn dip, a salsa or two, and guacamole.
For dinner, put out your already-bowled tomatoes/lettuce/shredded cheese/etc, warm some tortillas, and quickly grill/fry up some chicken and steak strips you've already marinated and cut. The appetizer bowls come in to round out the toppings. You can make the items as few & simple or many & interesting as you'd like, and since everyone's adding just the things they like, there's no excuse for complaining.
I hate the pressure of cooking for people who've been told I do it well. I find I then do much better if I choose something easy, and anyone who leaves happy with a full belly thinks they were told right!