No seams, no curling, no ribbing

I got started last night and I did decide to do fronts and back together with not side seam. I think the only way this might give me any trouble is in blocking, and this will need a good blocking because even my gauge swatched biased a lot. I'm also nixing the ribbing at the bottom. Moss stitch doesn't curl and I don't really want it drawn in there, so I just started right in with the moss stitch. I'll probably put rib on the cuffs, though. The other mod I'm making is with the stockinette bands. I'm making them twice as wide and will fold it in half when done, so it will have a facing and not curl. I'm using a DK weight yarn that really is knitting much more like a sport weight, so it won't be too thick there. The only thing I'm worried about is if I'll have enough yarn. Since I'm using a different weight I didn't know for sure how much to buy, and then I'll use more with doubling the bands. I hope I'll have enough!