You could address SAS Inst directly with your “best practice” question.
The architecture using a citrix server together with SAS I have seen couldn’t compete with a “traditional” SAS-client/SAS-server architecture (and it was a fast WAN). All point-and-click operations had a tiny little bit of delay – it wasn’t a lot but users weren’t too happy with it. I assume this delays become much worse on a slow WAN.
IT support was of course happy with citrix - the network guys didn’t like it too much.
What about having the most common clients (i.e. SAS EG) as local installation and specialty software like DI on citrix?
The point is: A lot of the work with SAS EG doesn’t cause any network traffic (most of the “code generation” work) and is therefore fast and smooth. The code is then sent to the server (that’s only a bit of text) and most of the results are kept on the server. It’s only when people look at results that they have to be download – so just make sure that the EG settings are in a way that result tables and the like are not opened automatically but only on user request.