I never go over 50% either. But, if I were in your shoes (with the specs listed above) I would definitely move all of it to the BT card. Utilization will be ~79%, but not near maxed out (90%). The util will go down pretty quickly and you'll save bookoo bucks. I say, "Go for it!'.
Note - Obviously, start PIF in the future
ETA - I just noticed 3 of the 4 CC's are already over 50%. Your score could actually increase after everything is transferred and reported. This could take a couple of months because of residual interest.