Comfort-wise, it’s hard to top the Arum dress. I decided to sew this one in a soft French terry knit. If you want to make Arum in this type of fabric, pick one that is on the thin side, or you might end up with too much fabric under the arms.
If your French terry is stretchy, you might want to go down one size, but you don’t necessarily have to. I cut this one in my usual size and the result is just loose enough. Since French terry has a tendency to roll up on itself, avoid using a facing for finishing the neckline and use bias binding instead.