I was also thinking of taking one of my tubes in the bay, but right now i'm just sticking with the kayak. I don't think that current would be that much of a problem, as long as the tide wasn't in a big swing. Like going from a minus tide to a 5ft or vice versa, but even then it might not be that bad. IMO what I would do is take off around the boat launch and stay around there or head into the back bay. I've never really heard of anyone flyfishing in the salt around here. Are you going to go for halibut? If so try the fastracs they're freakin awesome!!
-PHIL