swatching for doily

The Crochet-A-Long selected the "Design 555" from Celtwich site, it has 3 doilies. An oval pineapple, a star, and a swirl. Since we did a pineapple already, I've selected the swirl. Yesterday I spent swatching, trying to find the perfect combination of color, thread and hook. It calls for a #8 hook with #10 thread, but I tend to work loose and usually have to drop down 1 or 2 hook sizes. I don't have a #9, so I started with a #10 hook and light blue thread. Very tight and it cupped a little, so I moved up. The #8 and #7 I have are in-line hooks, so I went all the way up to a #6 and dark blue thread. The stitches are too loose, so I went to the #8 with the dark blue, the stitches look a lot better, but the thread is splitting badly. I'm going to have to go with the #10 hook until I can get out and buy some new Boye tapered hooks. So I try the #10 hook with a light orchid thread. Love the look, and finish about 15 rows, but it's cupping very badly. I pin it to the blocking board and give it a light steam and leave it pinned overnight.
Today I went out and bought 3 new hooks, Boye aluminum F, and steel 7 & 8. They didn't have a 9. Tonight, back to the doily