I just did so, currently testing with HRE on early...
It's getting an interesting play, i'm currently on high and i've witnessed the rise and fall (by civil war) of the French as superpower, greatly reduced on high by the resurgence of both English and Spanish, while the Hungarians killed the Polish and are now dealing with the horde along with the Byz, with the Italians becoming the amphibious assault masters after having killed the papacy... They will surely get headhaches later.
On the north the Danish are slowly expanding, having invaded finland and preparing to continue the assault on a surrounded Novgorod.
In the meantime the HRE (me) slowly but steadily expanded in central Europe, benefitting from rebellions in France and twarthing the English expansion ambitions on one side while keeping the horde remnants on the other...

I'm now approaching late and thinking about some more faction balance... Maybe the English will receive a slight penalty on Heavy Inf (CMAA doesn't really fit with their strategy, but we'll see) as they fare better with their historical units...