Seems like you missing whole point there. Also no one cares about free thumb ring as tatars? seriously?Free ballistics alone is relevant for like two minutes in the game until the other civ gets ballistics as well, then it's just some resources saved and 90% of civs save resources one way or the other. Pretty much any good bonus that lasts the whole game (britons' extra range/faster production, mayans' cheaper archers, chinese's cheaper techs, saracen's market prices, ethiopians faster firing archers, aztecs faster production, byz cheaper counter units, celts faster wood gathering etc etc etc...) is better. There is absolutely no way giving free ballistics to burmese would make them picked on the ladder ahead of britons or mayans or ethiopians or saracens or whatever if you want to play archers, it's like tatars' free thumb ring and nobody cares about that.
Also it's kind of a cruel joke bonus because you don't want to go archers with burmese anyways since no arbalest.