That's a very favorable comparison, I have to say, and a strong recommendation for making the expander.
I still tend to recommend building an SSM2166-based compressor, since it includes downward expansion onboard (and does a great job of it), but I suppose there can be circumstances where one wants the expansion without the compression, or vice versa. Mind you, given the manner in which the downward expansion is adjusted, it is probably feasible to use a SPST (or DPDT, since one likely wants LED indication) to enable/disable the expansion function. You can also switch back and forth from a minimum to preset maximum-compression with a similar footswitch, but the complication is that more compression comes with higher output level, so it is tricky to easily alternate between negligible compression (largely equivalent to bypass) and noticeable compression while maintaining the same average volume level.