I had a game with Prussia and got some thought during the game. It's hard, but it shouldn't be.
UHV1 asks you to have cities in one core, 2 historical, 1 border and 2 foreign region. If you do it properly you are around 0-5 stability in 1410. Then there is a big time gap, when you have to beat up every neighbor civ.
UHV2 is easier then it looks. I was the third in rank when it started. Muscowy were done, sweeden passed out, Austria died before, Germany respawned and cities were raised, Spain repsawn too late, so only France was left. And they never really attacked back, no sod were coming for me. Golden Age, ended before 1700.
Sometimes at my GA the great person counter disappeared. !?
UHV3 before I could care about this, in my capital I got 5 general and 5 engineer, very versatile. I only used 1 engy to build La Lanterna in Slopt. So this uhv might seem funny or new but it means you have to dump every GP in capital and its pointless.
OFC cheated a headquater for Teutonic Knights 'cause when I could expand them, nobody had it.
In mid game tax rate went down to 50% due to the big army and it crippled my research. I got my UU when the GA was over !!!! So imo we should make them earlier, i.e. replace the Pistolier! That its not so late as the last upgrade. UB, I could have it a bit earlier, but i focused on UU to have them. So public school did nothing toward my aims. Thus I built them in every major city, did not sensed any progress speed up.
Pls give more stability and a lot more border/contested zone! Taking Unstable cities kill the stability rapidly.
Ideas for 1.4: 15 GP thats to forget. Put something cultural/religious stuff here.
Map: rethink the lots of swapm in the region. also imo swapm remover tech should be reachable around 1350-1400!
The city is yours to take though 
