I don't iron my seams totally flat - my quilty pal always comments on that as she was taken under the wing of a more experienced quilter who thumped it into her head.
I waste thread at an alarming rate as I rarely chain-stitch. And I tend to be wasteful when quilting in general - I go with what is easier for me rather than what is most economical. Now that I am on a budget, that should change (in theory!)