I ideally want to combine it with Victoria Falls.
The Falls isn't really near any game parks, so just trot down there as a day trip. Book the hot air balloon if you can. It's also nicer from the Zambia side, although you can walk around.
I wouldn't go the SA now, Africa was iffy 30 years ago and it's not got any better since. Kenya is the main Safari location although you can see just about every animal in Zambia.
A walking Safari is a much better experience, driving around in a 4x4 will get you close to everything in a few days but it will feel exactly like driving around a zoo in a golf cart.
Most of the interesting things will happen while you sit by a riverbed and walk quietly through tall grass. We saw a dead elephant and a group of lionesses stalking an antelope, we fell over a pride of lions so don't worry about not seeing anything.
If you can, go right after the rainy season
Actually if you can hire a car, just driving around Africa is an experience in itself.
Anything in your luggage will get stolen or broken
I'd love to do the Gorilla trip but it's never going to be an option now.