Hikaru Muslin...

The next item for my wardrobe project is the hikaru jacket so today was spent sewing up a muslin to check out the pattern and the fit. (Please ignore the fact that I set the sleeves in inside out, it's not worth going back and redoing them!) Overall the fit isn't bad. It has plenty of space for extra layers (it's photographed with just a tank top underneath) but isn't too big.

The only fit issue I can see is the slight bagging at the back, caused I think because it gets caught up on my behind when I move around (if I pull it down it will sit smooth and not be pulling too much over my hips but as soon as I move it gets caught up again).

What do you think, is it enough of a problem try and alter or not really worth bothering about?

I have swatches of fabric to choose between from The Fabric Store (which is a convenient less than 5 mins walk from my house):

The top one is a dark olive green and kinda has the feel of slightly thicker felt. The bottom one is a dark-ish grey, is a bit thicker than the green and has a bit of texture to it. I'm erring more towards the green, what do you think?