I'm of the same mind. She sounds a bit too nice and helpful. Hope that she has some more aggressive attitude and a darker side. I like to think of her more as a fixer and less as a diplomat.
I'm going to disagree with that. It would make a nice change to have a character who is genuinely nice and who doesn't mess things up for the PC. I'm trying to think of companions/allies who did not cause trouble for the Warden or Hawke in some way and I can't really think of anyone besides Wynne (unless you count her lecturing as causing trouble).
As opposed to aggressive, I'd rather see determined and firm. We already have Cassandra to supply aggression. The key thing about Josephine is that she tries to get everyone to get along in spite of their differences. Remember that some of the members of the Inquisition will not get along: Sera hates Cole, Varric has trouble with Cassandra, Dorian and Vivienne don't like Solas, who reciprocates, and the Inquisitor him/herself may have a problem working with Cassandra and Leliana after they kept him/her prisoner and coerced him/her into working with them.
Josephine being aggressive would just undermine her goals of getting the Inquisition to work as a unified force.
I can see Josephine being sort of like professor McGonnagal, except more openly friendly.