I have to do a couple outfit, but it's currently a toss-up between two options, both of which are cheap & probably easy to piece together:
Football player & cheerleader. (jersey, shoulder pads, old cleats, socks & shin guards, source the pants. She has everything but pom-poms)
Arab man & wife. (cheap sheets!
Man &
Woman.)
We may play with the role-reversal, for the comedy factor, but nothing is decided as of yet.
I think picking a Halloween costume has a lot to do with a person's personality. Depending on what you're shooting for, there are a lot of creative options that can fit into a suitcase.