That sounds like a great trip! I think you should be pretty good with locking everything down like you said, the biggest thing is just make it enough of a pain to take that they will just go after something else, if you wrap it make sure what you are wrapping it with isn't going to flap on the seadoo or it will mark the plastics, for the trailer, if it is pretty new it should be ok, but I always put "bearing buddies" on the hubs and just grease them once in a while, definitely have a spare tire, and make sure you have tools to get the tire changed, if I am going on a road trip I make sure I have my battery impact with me and a torque wrench and a small hydraulic jack, it may be overkill but if I did have a flat on the trailer it wouldn't take more than 15-20 mins to change it out.