Musical Pete, if you enjoy rides that are designed with circles and straight lines, there are plenty of Meishos in Japan that seem designed that way. Take Camel Coaster http://www.rcdb.com/id1264.htm
at Nasu Highland. Personally, I enjoy the flowing curves of newer rides.
Yet, there are plenty of new coasters with straight line design, but in other countries (for instance, the Sameco company in China seems to use that style). I find it interesting that nowadays, the woodies seem to use parabolic hills only.