That is actually the second simplest way...ratchet straps are the easiest!
Bungies are okay if you are driving over paved roads. If you are wheeling you might as well have nothing holding the tire down. The bungies WILL stretch as they are designed to do (they work great for light goods). In the event of a big bump or the unfortunate event of a flop or rollover that tire has a great possibility of freeing itself and injuring the occupants of the VX.
NJ...nice work of keeping it simple. That is a great idea for those who have removed the rear seat. My seat is still installed and used so that is not an option for me.