Those of us who collect knits inevitably has some that have turned to be too thin or clingy and hug our rolls...
I have many of these and have used them as muslins so they have not entirely gone to waste but I have found that if you make a top a little bigger in size, it helps. What helps even more is if you double your fronts.
Do this by either making the second front a lining or by sewing the two fronts as if it were one (interline).
THIS MAKES A HUGE DIFFERENCE! I couldn't believe how much better this looks.
I discovered this one day when I was looking at some tees at Walmart and thought how clever. It took some figuring out and several tries but I worked it out.
When you use the second front as a lining you get the added bonus of nice clean neckline.