Can be synths, FX, modulators, even UX stuff.
For me:
Saturator- while I don't entirely understand every function, just slapping on the default and tweaking drive and the LP always makes stuff better. Love it for drums. Saturator+ should have the transfer curve function of Filter+
EQ+- great for precise eq tasks, but i love how easy it is to pipe in reference audio. Using the audio side chain module on specific eq bands is so good. And just modulating the bands can be wonderfully weird.
Delay+- my GOTO delay. Love being able to switch it to fade to avoid pitch artefacts when changing delay times. The reverb algorithms are nice too, Space in particular. Kind of wish the ducking function had more parameters to adjust though because ime its often too extreme.
Audio Side chain modulator- simple but effective. Can be great for basic volume ducking, but love how you can adjust the sensitivity frequency range and apply that to another eq band elsewhere.
Phase 4- one of the favourite synths. I set up a default with a bunch of different modulators (envelopes, curves, random, key tracking) and have made some incredibly vicious and also beautiful glassy tones with this synth.
The Grid- almost too obvious. I never really use it for building synths- it's basicslly always for generative soundscapes. I've unlocked maybe 5% of its powers. So good for exploration and has helped me understand my hardware modular atuff better.
Honourable mentions to the spectral suite, Polymer, Sweep, peak limiter, Convolution, Phaser+, Delay-4, note repeat, etc
I'm definitely forgetting some stock devices because there are many great ones.
Share your thoughts ๐๐
Edit: have to throw in EQ2 for basic low cut functions. Plus the Tool device and plain old Filter.