Zoom is important for Aftrica Wildlife
I went with several others on an Africa Safari. My recommendation is that you have at least a 200mm lens. Most of the great wildlife pictures were required closeups and animals are usually 50 feet away from the vehicle, especially the rare ones like rhinos. friends with low/no zoom had dots for animals. As for bulkiness, most of your time is spent in jeeps or vans with pop ups; so there's little carrying around of equipment. I took both a SLR and point n shoot. Enjoy!