I read an article in the Swedish Defence Reasearch Establishment's (FOA) magazine "FOA tidningen" that the U-boats of World war two offered pretty smooth surface cruises. They cut the waves like a destroyer, according to a cited submarine engineer, due to there hull design. While modern subs shaped more or less like tubes rolls so easily that even small waves makes a surface cruise less than enjoyable. I guess that is the only thing that was better back in those days.

I recommend the second issue this year of the "Foa tidningen" for those of you who understand swedish. It has several articles on submarines.