Finished yesterday one big 43Civ game with the Songhai. The game went all the way to long science victory.
Unfortunately due to early lack of horses, I couldn't unleash the Mandelaku cavalry. I had only two horses for much of the early game so missed on the fun of their unique unit. So yeah keep that in mind, resource dependent early on. Until I had enough horses, the Mandelaku cavalry was outdated.
But the tabia building is well worth it for early production and I also had very few roads, which helps control road maintenance.
Fast exploration along rivers, fast fast movement along rivers, crosses rivers without ending turn, quick to place cities. That is good, helped me capture Rome early on. But again terrain dependent, if there is no a long river at the start, you should probably reload.
Strong Civ in my opinion, consistently scores above average in AI hands as well. Hope you have horses early on for maximum fun.