The flaws, funnily enough, can help you like them more and certainly should make them more rounded characters. But given with most people there is always something you can like and dislike, this should be true of your creations too.
With my rebellious fairy godmother, Eileen, I both like her outspokenness (her honesty makes her what she is) but I also dislike the way she can and does ride rough shod over those who don't really deserve that treatment. Eileen cannot switch that outspokenness off (though she would be more likeable if she could do so).
In listing likes and dislikes of your characters, you are getting to the heart of why you are writing them that way. And it can be a useful way of working out whether those likes/dislikes are justified based on how you have written your characters. Also are your characters coming across on the page the way you meant them to do?
In having likes and dislikes your characters will be more real to you and I think that will show in your writing.