First talk to your PH and ask for details. The EC is a huge place with a very wide variety of environments.
On my first hunt, which was in several parts of the EC, we were always watching for a good wart hog but first off it was not a good time of year. It was still hot so the big boars were mostly underground during the day. We did see a couple big bodied ones early mornings but they had broken off tusks. It was very rocky areas. Didn't get one but shot a cull the next trip. Finally got a big one in Limpopo and a bigger one in Tanzania
Springbok or springbuck are desert animals so best hunted in the Karoo of the EC or the Kalahari. I truly enjoyed every Springbok hunt I've been on but the wide open areas where they are endemic are always best and the most fun
Both are worthwhile trophies. When I shot my first i looked at the PH and said "that was fun, let's do it again! He was game so I shot 3
Don't overlook a trophy blesbuck. They should be priced reasonably in the EC. Black Wildebeest and Red Hartebeest are a couple of my favorite PG, especially in the EC. Consider them. And don't write of a trophy Steenbok or duiker. They go well with a buffalo
And to really add to your hunt, do some night hunting! If you get your buffalo early in the day, go in and celebrate, rest up... and if you don't celebrate too much, go out that night! Take a simple predator mouth call. Or record some dying rabbit and squeezing mouse on you phone. That is if your PH doesn't have those. Calling in jackal is a blast! You may get a Caracal, Serval, Civit or even a leopard to come in... exciting experience! Maybe not a leopard in the EC but in Limpopo I've had it happen several times

South African is crawling with big leopard...