Had a ton of bad rulers (in whose honor I named my single colonial nation, "BadRulerBurg"), and about 70 years worth of regencies. I got only one PU, through war, with Burgundy.
The last 120 years or so were mostly border tidying and vassal absorption. Tag switching to the HRE obviously would have made things considerably easier, but I didn't wanna. I
may load up the game again and tag switch to Germany just to see how much difference the accepted cultures would make on my manpower/income.
There are a lot of things I could have done better or faster, but it was a fun romp.