Honestly I didn't think too much about the advisers individually. I suspect for me it's largely to do with the fact that whilst with playable companions you have to chose them individually when you go out on missions, whilst the advisers always felt like a collective group (except Cassandra), especially when you get visible approval and disapproval reports for your playable companions as opposed to your advisers.
Furthermore, whilst I reckon I could figure out some contrasts for the advisers, e.g. Cullen's attempts to escape his past through breaking his lyrium addiction contrasts to Josephine's efforts to regain her family's past status, to be honest I feel that I'm reaching to a much greater degree than in regards to the playable companions, especially as I feel it makes less sense for the four advisers to have been designed to contrast one another, simply because they need to work together willingly to make the Inquisition's rise to power make sense. There's also the issue of who goes with who with the advisers. Does Leliana and Cassandra go together simply because they're the two hands of the Divine? Should Cassandra even be counted as an adviser, considering she doesn't lead any particular section of the Inquisition (as far as I'm aware of)? If she isn't considered one, should Leliana therefore be contrasted to Cullen, especially as she leads the spies whilst he leads the forces?
To put it simply, I felt dealing with the advisers in regards to contrasts was 1) going to end up stretching for contrasts 2) be a bit questionable regardless on who you pair with who. I mean, for me I see Leliana, Cullen and Josephine as joining you as a group when you reach Haven and I'll admit, I didn't think of/remember Cassandra as an adviser.