about half hour by ferry

I'd prioritize them and do the one I am most interested first and then just see how it goes. My philosophy, even thought you didn't ask is that my vacation means not adhering to a schedule. Having a list of options and just seeing how it goes is more fun than trying to fit too many things in having to rush rush.

I think the master glass blowing demonstration in one of the factory on the island of Murano is free. But you need to check the time when demonstration is given to the public.

If you want to swim you should head over to Lido where there are beaches on the Adriatic side of the island. We were advised that the water around the main islands in the lagoon was too dirty for fish to live, or for bathing. Lido public beaches are your best bet and are accessible via a water bus from Venice to Lido.

Sicuro, il giornaliero vale per gli spostamenti da e per le isole.