I hate ambiguity and value being asked out or asking someone out rather out right.
The whole, "maybe we should hang out sometime" bit is something I would see as a turn off, honestly. Not sure if it is a friendship, hookup, or friends with benefit situation if we are to just hang out.
First, I figure out which kinds of foods he likes, and lead in with, "can I take you to dinner? I know a good [sushi/Italian/Mexican] place."
Also, if you're gonna ask someone out, have something in mind, whether it's coffee, dinner, or a concert, don't just ask someone out but then not have anything in mind.