If you want to get the good ending, ideally you'd do WM2 before the end of Act 2, for story reasons. But that's hard, and annoying, so I usually leave it for last. And it's not like the good ending in WM2 matters much when you import your savegame to PoE2.
Didn't even know there are multiple endings in White March. Fun topic to google/youtube later.
It is indeed fun, the whole dynamic between Ondra and Abydon was more interesting than relationship between other gods imo. Sadly, it doesn't have a big influence on PoE2, other than being able to talk shit to Ondra once or twice.
However, tempering Abydon (which can be described as the good ending) is a bitch because you need to present six perfect arguments (two for each catergory):
- That history doesn't always serve progress or provide a good example;
- That memory can be a burden, and;
- That some knowledge should be forgotten due to the inherent danger it poses.
Two of these are tied with Aloth's quest and the animancy trial, and most players will actually make a choice that doesn't agree with the thinking of the Eyeless, thus making this almost impossible. So it might be considered a good challenge to finish WM2 before ending Act 2, just to see how the story unfolds.