Self esteem is more important than looks. You could be the most gorgeous person in the world, but if your self esteem is low, then that makes you unattractive.
Be content and happy with who you are and what you have, and others will feel it. You must first accept yourself before you can expect others to accept you.
Anyway, in response to your question, it depends. I could not marry someone who repulsed me, sorry to be frank. But someone average looking, but with a great personality and characteristics, is be a million times better than someone who looks great but has the personality or intelligence of a rock.
And of course, everyone has different perceptions of beauty, there's someone out there for everyone.
Here's the question though, would brothers marry a sister that wasn't good looking, if she was a good muslim and had good akhlaq? From my experience, women are wayy more lenient in the looks department than men are.