I love Doug(Kevin Nealon) as well, but my favorite character is Andy (Justin Kirk). I think that Albert Brooks will be good too. However, I could do without Shane(Alexander Gould).
Also, here's some info from wikipedia
The first episode of this season entitled "Mother Thinks the Birds are After Her" is the last time "Little Boxes" will be used over the opening credits, after which it will be replaced by new credits and an unknown theme song.
From what we know, the show is taking a whole new direction. Showtime has guaranteed that the show will still contain the iconic dark humor that is loved by the fan base. However, the new setting will affect the coloring and overall atmosphere of the series.