You can easily spend a few days at Vic Falls. I would definitely recommend white water rafting... very exciting. Although if the water levels are low, then the rapids will be much more "violent" as the water's surface is closer to the riverbed and the many obstacles over which the water must flow. I spent a day rafting and had a blast. The gorge is beautiful. We had lunch along the riverbanks, went swimming in calmer areas and pools, then hiked out of the gorge and found a big meal waiting for us as the sun began to set.
On the river above the falls you can also go kayaking... in contrast to the rafting, you have more time and chance to look around and admire your surroundings. We also once come across a crocodile sunning itself only a few metres away on the shore!
The bungee is fun if you like a very quick (and intense) thrill. It is one of the highest in the world in a spectacular setting, so much more worth it compared to fair grounds where you just jump off an ugly crane. Worth it if you want to bungee jump once in your life, but otherwise I would spend the money elsewhere on more lasting memories.