One would think that an AI like Catherine of Russia would perform better in this respect but for some reason Hiawatha almost consistently out-spams the Russians.
That's because of their start biases. Hiawatha starts in forest : Hammers!
Catherine starts near Tundra.
In both cases though, if the human is on Prince both of them do outrun their happiness bonuses provided by the "AI Default Handicap"
It's only on Immortal & especially Deity which gives big AI happiness bonus on top of that in which they'll stay in positive happiness. But the other AIs will be nearing Suma Tablets for everyone at the same time; so it's still not free, those two have had a lot less Golden Ages than the other AIs.