I loosen the battens and the out haul to preserve the sail. I use a key to tighten the shackle on the jib clew, but not the jib or main heads. I believe there is so much force on the heads that a key is not required. On the jib clew, lots of bouncing around with no force.
Not sure what to say about the jib tack quick pin prohibition. Is that a class rule?
Regarding the rudder covers, you should certainly keep those covered until the end to maintain form and protocol. Of course, if you don't have the right race attire, then keeping the covers on will not help much.