
Rigal's book I feel is the "next step up". I liked how Barry wrote it with some substance in terms of a "global" approach with conventions, system, and such. However I agree with Richard; the relays part of it is very substandard and poor.
From there, I think it would benefit you to view Blue Team Club's methods and other five card major methods. The sky's the limit, and you'd have the foundation to understand the complexities and digest them. I feel exposure to styles and such, can only be fully experienced, once the fundamentals and infrastructure is understood and realized.
SH: Thanks for the advice, I'm having the same problem with pages
falling out with Hardy's 2/1 book. Maybe I can graduate from Berkowitz
to a book with a better treatment of relays. I've looked at the notes for
Garozzo's system for World Itatlian Jr. team, Sontag/Bates and Meckwell
and I agree that a foundation is required.
I will need to find somebody to practice with on BBO, perhaps the player
profiles will help. I thought the Antipodean Club to be quite creative, and
the idea to read the Bermuda Bowl book seems very good.