Would it even be certain that the United Party would be formed, given South African politics will be different from at least 1909 on? Perhaps, for an example with relatively minor changes, you could see the Unionist Party be strengthened enough that when it merges into the South African Party it...
I think part of me reacts positively to fix the Draka TLs as a counter-reaction to the argument that the Draka are simply the bad guys getting all the benefits and breaks the good guys usually get in stories - stories tend to have the good guys get all the breaks during the narrative itself...
A war between Ba'athist Iraq and Pahlavi Iran (starting) in 1975 seems like it could be an interesting story in its own right (could it give the Shahdom a lease on life? Could it derail Saddam's rise to power?), although not one where Saudi Arabia getting toppled by a reactionary anti-monarchist...
It honestly sounds like it could fit in a 1990-based retrofuture (the USSR is around, but the Cold War is over because the Soviet Union is just Another US). I'm suspecting it is using a different definition of liberal, though.