I think throwing a bbq party depends on how many people are going to be there. Are there kids, or are there vegetarians coming over too. Most men like meat more than sides. Kids love hotdogs and burgers. I think steak are a little expensive if you are feeding a lot of people. So I'd go with tritips sliced it and it will feed a lot. I would also do bbq chicken. Chicken is always a safe bet for every one. As for the sides, potato salad, corn, coleslaw,potato chips, assorted fruits. I think 5 or 6 sides would be plenty.