I've been pondering your question because I'm just starting to do some of her blocks (but not the butterfly quilt). The only thing I can come up with is to go and do the blocks. Then, if you can, bring them home and do what PaperPrincess says. Use a design wall and make your own design using the blocks and some sashings and/or plain blocks. Or perhaps you can take the design wall with you when you go and work on it there. As for a design, it's a matter of personal preference. For me, I'd probably do something more circular or spiral-y. Tula's blocks incorporate all kinds of prints so I think your civil war fabrics should work just fine. Have fun creating your own quilt!