Best way to reuse circuit modules

[Harvs]

I'm now in a job where I'm doing a lot of one off test rigs built reusing lots of "chunks" of circuit design.  A simple example would be a layout of microcontroller, decoupling caps, crystal and programming header.  But some stuff I want to reuse is much more complicated.

So the question is, what's the best way to do this in CS?

About the only way I've come up with so far is to create a separate project which I'll put a schematic sheet and pcb for the module, create the schematic and layout the circuit.  Then copy the schematic sheet into the actual project I want to use it in and create a schematic symbol in the main schematic and link it up.  Then copy and past the circuit layout into the PCB prior to updating changes and resolving any errors.

Surely there has to be a more reasonable way to doing this that I haven't found yet?

[technotronix]

Some of the things to consider while reusing circuit modules are below:

Avoiding potential signal integrity or thermal problems by using circuit data with proven performance.
Reduction in time taken for schematic capture and PCB design leading to reduction in development costs.

[Harvs]

If I'm not wrong, it would seem this functionality was called "Snippets" in AD, and has been removed for CS.

But it doesn't seem like it was all that well linked up in AD anyway, so I guess I'll just use a manual process of copy and paste from a "library" pcb project.