In Northern Europe, Loki was a clear-cut villain.

He was? In the Eddic literature, he's certainly not: the city of the gods could not have been built; without him, Thor's hammer could not have been reclaimed from the frost giants; and he must have done Odin a good turn indeed for him to consent to becoming a blood-brother and thereby numbering Loki among the Aesir. Yes, he did many bad things, but let's not forget the good - that's why Norse scholars have such difficulty with Loki.