I think one has to cut old series some slack. I tend to find they come with slower pacing and can be very set-bound in some cases. That is partly because the old cameras used to be much bulkier. However, I think the acting is often better than today so there is some trade off.

The Baader-Meinhof series is good. I enjoyed the film they made about them some years ago. I was impressed by how nuanced it was, i.e. showing all the various angles.