I've got a working rig by following along SideFx's rigging tutorial, which was excellent. but im wondering how to take it further. from what I understand its only a basic rig.

I haven't found many more resources on rigging in houdini but would like to take it further.
Ideally i'd like to be able to make a rig that I can adapt for different characters, preferable one with a single HDA i can make changes to that would be reflected across different versions of it

that is the function of the Autorigs:

https://www.sidefx.com/tutorials/autorigging-masterclass/ [www.sidefx.com]

you can do things like this on your own if you're comfortable with python.

ah I see. I was avoiding autorigs specifically because I thought the autorig wasnt “advanced” enough and I wouldnt be able to do more than basic things with it.

Thanks for you reply!