In my experience so far with Kongo (although not at deity), the trick is to spam Commercial Districts and Theatre Squares for the GPP and postpone other districts. If you have good production in your capital, the Oracle is nuts, no one is going to beat 6 GPP/turn early game. Once you have your Palace filled with Great Works, you fly through the Medieval and Renaissance civics, most of which have very convenient boosters. Also, Great Merchants + fast civics + early t1-t2 governments means you will have a lot of envoys, so your districts produce more, and you can levy an army in case someone attacks you in the middle of the game before you hit Civil Engineering and Nationalism. Fast civics also means you'll have spies before other civs and more of them.