1. Just get some stretchy cord/string from hardware or boat supplies and you can tie down stuff when you want to cruise for a long way. (E.g. a water bottle or a dry bag with your phone/camera/snacks ... or a six pack of Coronas... or whatever).
2. Not my area of expertise, but I believe a lot of the bigger SUP joints also help out with the sail side. Try www.surffx.com.au/windsurfing/
3. Nice board. I have one of those as well. Weighs approx one tonne, but surfs great in the small stuff, stable as a table, and paddles like a dream.