Tobias is also pretty high up on the list for me, as well as Lucille, who I think doesn't always get as much credit as she's due. Anyway, I'm very happy to hear that we're finally getting another season of this show in May. I had pretty much given up on ever getting more, to be honest.
I looked into it a little more after reading your post and the new format sounds really interesting. First of all, it's going to be released on Netflix. And apparently, each episode will be devoted to a different character and show what happens to them following the season 3 finale, making it possible to watch the episodes in whatever order you choose. Michael is the only character to appear in every episode. What do you think about this? My opinion is that it could be brilliant... or it could turn out a little too much like endless eight. xD But I am guessing they'll find a way to make it not so repetitive... hopefully.