Excellent points! Thank you. I had to give up my Gold Wing Aspencade (1500cc) due to the need to ride constantly as if I were doing the splits thanks to the horizontally-opposed engine cylinders so spread-eagle riding won't work for me. I can just stretch out one leg at a time, though. Right now, I just hold a leg straight out to the side but that gets really old in about a tenth of a second.
If the floorboards don't raise my legs too much, it should be okay. I have a 33" inseam. In fact, most of my height is in my legs and I'm 6'1-1/2".
And, having been a knee-squeezer since my first Spyder (2010 RS SE5), being able to press down on the boards will be an added advantage.
Thanks so much for the added insights!
bc