I think it would be fine to move the rigging area but access to the river is more important. The STEPS OF DOOM SUCK!
A launch like they have in Hood River at the windsurf park would rock and if it was accessible from the rigging area that would be even better! Which would save having to navigate your way through traffic. Not sure if that's possible though? I didn't buy a pass this year because of the launch and as with Brian sailed out of Nexen when I could and only went to the spit 4 times.