Hi Shayna, welcome to the board.
You will get as many answers as there are batting choices.
First it would help if you specified are you hand quilting or machine quilting. Then you need to decide how closely you want the quilting to be. Some battings require quilting as close as 2" and others as far as 10". Do you want a natural or synthetic batt or a blend? How much loft do you want? Is the quilt meant for a fairly warm climate or frigid northcountry winters? Do you want a lot of shrinkage once the quilt is done and washed for the first time? (that crinkled antique look)
There is no "best" batting. Batting is dependent on all the variables I have listed above. You need to decide these factors before any of us can make a reccomendation to you.