What Are the Drawbacks of High Misfortune?

[Twan]

All these events may happen with low misfortune and some even with luck 1 if as a player you are unlucky, so taking misfortune 2 or 3 has no real special drawback.

I like to play with luck scale because it's fun, but I don't think it's actually balanced at all.

I think the main problem of the luck scale is the cap on the number of events coupled with the fact you usually own some provinces where your scales aren't maxed. So if you play a big empire with luck 3 turmoil 3 and are conquering new lands at the fronteer of your dominion, you will often get bad events from provinces where you have only turmoil, and these events will count in the maximum of 3 events per turn in your national provinces, limiting the benefits of luck.