You missed Stucco and Perluis? I only played Gobliiins 4, and I enjoyed the teamwork, though none of the characters were well developed -- partly because the dialogs were kept to such a minimum, I think.
I thought the characters in Deponia were well developed on the whole. We didn't learn much about Goal since she wasn't conscious until near the end of the game. I think it could be amusing, seeing Deponia and Rufus from Goal's eyes.
I like playing from different perspectives if the characters have very different personalities. Especially where the puzzles involve teamwork in which individual talents or abilities come into play.