Well, after looking at the shape for a while, I ripped it all off and laid out the splines differently. The previous shape had a flat spot on the front of the cowl. If I did not have to make the nose work with the existing cowl, I would have gone for a different shape all together, but I didn't want it to look like a complete afterthought...

I have a large picture database of fast planes, mostly Forumula I planes since they are similar to the Sonerai. I spent some time going over the different cowl shapes and decided to go with a sharper look.

The shape now converges on the 2x5" cooling inlets that start at the base of the spinner. I extended the shape onto the spinner so that the inlets will open flush with the shape. After the glass is laid up, the front edge will be modified for a more rounded shape.

The splines now converge on a center spline 

They attach to the center spline with solder

The splines now angle directly aft on the cheeks

Side view of the new shape