Loving heavy compression and side chaining as stylistic element as used in Low’s ‘Double Negative’ (https://lowtheband.bandcamp.com/album/double-negative) or some Colin Stetson records. Big fan …
In the modular I tend to use side chaining on parts of the mix (e.g. long delays, either side chaining the delay input signal agains the delay mix out or percussive/kick elements agains the whole ‘voice’) to clean up a bit. Usually with on board tools — envelope followers, attenuverters, VCAs.
For more percussive elements I also compress/limit a copy of the signal and mix it back in with additional reverb. Nice effect. Sort of a ‘room mic’ thing …
As mentioned in the original post, I feel, often synths are very constant in dynamics and don’t need compression as such, but I like to use it as glue. It really works for bringing sound sources closer together, making them feel as ‘one’.
That said, I sometimes like to use the inversion of compression (also mentioned here already), expansion. Multing a voice trough an envelope follower and the resulting CV into a VCA (with offset/attenuation for more control). One of my favourite effects, actually …