I haven't seen this weeks yet (saving it a week), so this might all change...
I really like what they're doing with him. It's unlikely he'll get a happy ending, but this is the closest we've got to seeing that he's capable of change and growth (especially in his last couple of scenes with Sally, don't think we've seen him be honest with anyone like that away from Anna Draper). Before he would have just stropped and given up on the company, but he seems to get that his work makes him happy and he needs to actually make some sacrifices to get that part of his life back.
Peggy's become someone who devotes her life to her work but gains no happiness from it, especially as she's hit the glass ceiling in that world.