I was a late bloomer in any number of ways. I started med school at the age of 33, and had never had a serious relationship to that point. After starting school, I met (and subsequently married) an absolute stunner in my class who has turned out to be my perfect match in every way. If some kind of personality flaw is what led me to stay single as long as I did, I thank my lucky stars for that flaw, because things have turned out about as perfectly as I could have ever hoped. Of all the crushes, flings, and failed attempts of my 20s, there's not a single girl I think back on and say "man, I wish that relationship had worked out instead."
Being flawed is part of being human. It's unavoidable that we all have our "red flags." The point isn't to try to be perfect. The point is to figure out how to be happy despite our imperfections. I have my flaws and I've made my mistakes, but I don't really regret a thing because it's all lead to an absolutely wonderful life.