Oh believe me, I am a HUGE fan of tactical knobs - I still get a ton of mileage out of the synth I learned on, the Aturia Microbrute (which I still highly recommend as a cheap first synth). I think having that immediate feedback of turning a knob and hearing the change makes the principles stick better for a lot of people (myself included!) I've looked into the Werkstadt myself - seems like a great piece of gear for the price. One of my absolute favorite bits of gear is the Koma Field Kit FX, a modular fx kit. I just built some CV touchpads to control it using this tutorial, which also works with my microbrute. There are tons of great DIY tutorials online for modular synths - if you're looking for a hobby that will swallow you whole, I recommend it. Good luck with the Poly D, seems pretty intuitive! And it should mostly line up with my tutorials.