I think it entirely accurate to call him a trickster. It's less accurate to call him a god. He's neither aesir nor vanir, and all sources give his mother as a jotun, and either don't mention a father, or mention a jotun father. Granted, he's "blood-brother" (that is, they slit their wrists and mixed) with Odin, something that saved his hide more than once. Granted, what is and isn't a god in norse myth is a bit fluid, and seeing as he is the father of the godess of the underworld...gah, this stuff is confusing. Even contemporary sources are a bit iffy on that issue.
I agree, his role is to be a spanner in the works, whatever the works may be. Depending on the story, he can be an evil trickster, or your slightly nuts bro who's fun at parties. He's definitely not a satan figure, his goal is never antagonism (that is, he's not siding with the opposition, he's just messing with both sides) or corruption, He's basically a mythological internet troll, stirring things up to see what happens.
Also, while he's responsible for Baldr's death, it's more accurate to say he arranged for him to die, rather than killing him himself.
_________________
I'm bored out of my skull, let's play a different game. Let's pay a visit down below and cast the world in flame.