Since we have semidesert terrain in this map, I think that we should try to avoid having plains/savanna/steppe directly touching desert tiles, both for cosmetic (it looks better/less abrupt transition) and geographic realism reasons (it's very rare in real life to have a direct transition from plains to desert without some sort of scrubland.
Also, the Kalahari should have much more semidesert in it, it's far more of a semidesert than it is a true desert.
I'd also recommend adding 1 tile to the east coast of Great Britain, for a more aesthetic coastline, and either adding another tile above the current diagonal Cornwall tile, or else replacing the diagonal Cornwall tile with a tile above it, I don't know how to access this map, so I can't test out possibilities myself, sadly.
As far as setting up the map for city placement, I think South Africa could now accommodate at least 5 cities (Cape Town, Port Elizabeth, Durban, Bloemfontein, and Pretoria) without being too crowded, as much as I'd love to have all the important Boer cities, it doesn't seem to work on this scale. I read through this thread before I made my account here, and now I can't find the specific post, but I saw one that proposed expanding South Africa by adding an extra row...this could be a very promising idea, enabling a third city for the Boers, if they are ever added in. One potential idea for a Boer civilization is to have them start with settlers near Cape Town in the 1830s, and have them have to move the settlers to the Boer Republic areas while avoiding independent/native/barbarian impis, instead of just spawning settlers in Bloemfontein and Pretoria. Perhaps, given the prominence the miracle at Blood River has in Boer culture, one of their unique units could be called the Voortrekker, and it could be a settler with combat abilities, and when it settles, all of it's XP could become free production/culture/gold for the city it founds, maybe at a rate of like 1 XP point to 100 production/culture/gold points. That would be a unique gameplay element for the Boers, and could encourage them to battle a few impis with their Voortrekkers before settling, as opposed to just beelining to Pretoria and Bloemfontein, essentially making the Great Trek and Blood River a real part of the game.
A unique ability for the Boers could be "the Power of the Bittereinders" - for every Boer unit destroyed, all enemy units in southern Africa lose 10 HP, for every Boer city captured, all enemy units in southern Africa lose 50 HP, but for every Boer civilian unit capture by the enemy, the Boers gain extra war weariness, a reflection of how the Brits won the Boer war by capturing and imprisoning innocent Boer civilians until the Boers capitulated to spare the lives of their families.
Overall, this new map creates a real potential for a unique and fun Boer civilization in South Africa, which currently has no playable civilizations.
Boer diplomacy music could be Sarie Marais or Die Stem...Sarie Marais would probably be better, since it was written during the Boer Wars, whereas Die Stem was written after the Boer Republics were destroyed.
I'm very excited to one day play with this new map, especially in the South Africa area. South Africa looks so much better on this map than on the old one. Great work to the people who have made this new map.