I use exactly what Scott said on a lot of different things, coincidentally.
And as tacky as it first seemed to me, I really enjoy the taste of McCormick's Grill Mates Montreal Steak seasoning. I buy the bulk shaker from Costco and have been using it for my last 3 or 4 tri tips. Also used it on some NYs and some rib eyes. Goes over very well. Simple, but good.
But if I'm putting something together, it's garlic powder, onion powder, paprika, salt, fresh ground pepper.