you won't need the full fleet to fend off any neighboring country – and as I said they offer the whole range now: from small prop-based CAS to state of the art (at least for everyone non-NATO, China or Russia) air superiority.
And I wouldn't really worry about the amount of cash available in such conflicts. In the past it generally was enough for leaders to bribe their way into being accepted citizens of the western hemisphere, see here: https://en.wikipedia.org/wiki/Isabel_dos_Santos
Now suppose, EU drops any support for the angolan government, she wants back her power: probably easy for her to start a civil war. Some neighbors (Namibia, SA) might step up (like they did in Somalia) to help the government if it holds out the initial 1,2,3 ... weeks. Normally they would have uncontested air superiority. Now Ms. dos Santos asks Mr. K.: "How about 4 of your hornets, I heard they kick ass, do you want some diamonds?" (and yeah, they can easily operate from a number of airfields there, I just counted >20 of more than 2km lengths of asphalt: https://en.wikipedia.org/wiki/List_of_airports_in_Angola). And that is how private contracting basically already works for advisors/spec-ops – great to see that extended to state-of-the-art aircraft.
Really great, good progress, all hail the capital!