That's a question only you can answer. What would attract *you* to a web host over others? What things made you choose the providers you went with? What have former (or even current) providers done, or offered, that made you think highly of them and / or their services?
Think about what things you would find admirable or desirable in a web host (what would make you choose one over the other.) Then figure out of you can offer that whatever-it-is. Then, if you can, figure out how you can tell others about this distinguishing feature (often one of the more difficult bits. You have to find a way to advertise it so that it makes sense, but doesn't make you or your company come off sounding like you're saying "We're better than all of those rebel scum." [Though that particular tag line might net you some of the more hip, sarcastic old-school Star Wars fans. Who knows?] )