While hoisting the sails keep them on the trampoline. With a 16 you do not need to zip the jib to the forstay so you can just hook up the halyard to the head while it is on the trampoline. On a day when there is very little wind you can hoist the jib before you attach the tack to the chainplate.

As for the bag, just make a bigger one. It is not really good for the sails to be rolled too tight. It is really easy to make another if you have even the slightest understanding about how a sewing machine works. You may want to make one for the main and use the one you have for the jib. That is what I do with Hobie sail bags.

Later,
Dan