Thanks for the comments guys.
sgl, I am glad to hear that coming from a Bonnie, you are getting the same thrill on the Thunderbird. I do love the Bonnie, it's a fun little bike. I just keep thinking I wasn't thrilled on the Tiger...similar to your feelings from your BMW, sounds like. The Thunderbird, I think, would be fun every single time.
Daz, yeah, I would like a little forward lean. I need to take a longer ride on the Storm, maybe my feeling was skewed a bit since I had just jumped off of the Tiger. I was thinking the feet forward controls were causing the rolling of the spine, as I am used to having my feet under me. Maybe a change of the seat, and just getting used to the position would help. A test ride should provide more answers.