I'd like to see a Red Dead Redemption episode/total conversion set in Africa during the Boer Wars.
It could be a prequel following a young Jack Swift in his military days or as a mercenary/explorer/Big Game hunter.
All they'd have to do is alter the environment, change the Mexicans to Africans and the Americans to British and Dutch, and change all the animals to native African species.
The core gameplay, i.e. riding around on horseback, shooting things, hunting (treasure and animals) could remain the same, they'd just need to alter the setting.