All my "blocks" directions are sew first cut later. That is what I call my cut down method. I love it as you get tiny piecing without handling tiny pieces.
I have never had the guts to try velvet and lace etc. I know they used to use alot of that in crazy quilts in the "old" days. I admire anyone who can sew with silk! I have had some fabrics that are slick and I hated sewing with them. But I am used to only cotton. So if I did it on purpose it might be a differant story. I would be prepared for the slipping feeling instead of frustrated with it.
I have made stuffed hearts with velveteen fabric. I love how it looks and I like the stretchiness of it as I made some teeny tiny hearts with it. Hope you don't mind a pic on your thread. But this is what my hearts look like. Some of the littler ones are less than an inch. My mom is nuts over hearts for Valentines so I play around with a lot of differant kinds closer to Feb. every year.