HI FROM A LONG TIME AND BIG STASH QUILTER!
Don't buy too much fabric when you first start, your taste will change as you see more fabric, and get better and better. Finally you'll say when you look at your first fabric purchases....."what was I thinking?" I do think that what you are doing in only buying small quantities is a great idea. I have had to give away so many of the fabrics I first thought were so wonderful.........! You will find that different thread counts make a difference in the fabric finish, the type of dying, etc.
But have FUN and learn about fabric as you go along and discover your favorite fabric companies and types of fabric!
One thing I had problems with is making myself use a beautiful fabric that I think is too good to cut up! What has helped me get over that is that my best friend and quilting partner died with all her beautiful fabric left......I cleaned out her studio and have all her glorious fabric that she was too afraid to actually use! I realize I don't want to die and not have used all her, and my wonderful fabric in a quilt that would be loved by a relative or friend. If you buy it......use it!