Man, I only tried MP Europa 1400 a couple times. It was a blast for a bit - it had a bit of the feel of an Imperialism game - very cutthroat.
Biggest bug I remember was the people you condemned to be burned at the stake weren’t actually killed. Later fixed.
As for guild 2 I think I bought 3-4 expansions (didn’t get pirate one). It’s less buggy than the original. My main complaint was the design - they changed it to be more of an RPG/Sims style where you controlled founder, wife, children all in real time. It was kind of fun to make the eldest son be a murdering thug who waylaid passerby outside the town borders but it was stressful to play in real-time mode.