Top sirloin ideas
Fire up the grill.
Give em a simple dry rub - coarse black pepper, ancho, garlic, onion powder. No salt.
Don't you dare cook them past medium. Sprinkle some salt on while grilling.
Compound butter would be nice. Maybe a chive/garlic.
Melt a bleu on top?
Top sirloin is one of my favorite cuts. I don't think much needs to be done. KISS method definitely applies, IMO.