Hobie Cat suggests that the rigs should be tensioned to help prevent impact loading on fittings. When loose, the rig will flop around and possibly cause jolting tension on fittings.

Mast rake aft will help keep the bows up when reaching. Typically rake will assist in pointing ability as well. The limitation on mast rake is the mainsheet blocks. Too far aft and you will not be able to sheet properly.

Hull cleaning? I suggest a soft scrub with bleach in it.

Trampoline cleaning? Same, but for really nasty stuff I have used a small amount of Easy-off oven cleaner in water. Be sure to remove the tramp, place on concrete, keep the water running, use a brush, Rubber gloves and eye protection. Amazing.