In my escapades, I have found that for me the most desireable and noteworthy trait I need in someone is honesty. Everything in a relationship derives from honesty and nothing cannot be conquered if 2 people are truly honest with each other.
I agree, honesty (and the good communication skills that go with it) is SO important!
But I also think relationships are a balance of a lot of important qualities... not just one thing. Because you could be 100% honest and still not be compatible.