The Salmple might be overkill if you don't want to record on the fly, for example.
-- plragde

This is very true. If anything this would be the module that I could forego in this initial setup. The caveat being I wouldn't be able to utilise samples/drums when using the rack standalone. I don't think I'd want to sample on the fly, but I'm not entirely sure yet.

In the video thumbnail, one can see that the Pam's is pretty much maxed out. Adding modulation sources and ways of transforming and combining them might be something to consider.
-- plragde

Maths would be the next module I'd buy with this setup. I suppose I could even replace the Salmple with the Maths first. I'll have a think about it and do a bit more research. I think as a start, I'd definitely get Plaits, Digitalis and Forbidden Planet and maybe go slowly from there?