For most people, wool - overall - is preferable to cotton, at least in warm weather hiking conditions. However, it sounds like you've given both types a good try, and you have come to a different conclusion. So ... my advice is to go with what you know works for you.
You might consider bringing an extra pair (or two) of whatever sock you choose. They weigh almost nothing, and on a long hike putting on a fresh pair about 2/3's of the way thru can make a big difference in comfort level.
