Yes, it will be floss. I've still got a way to go to fully flesh it out, but I'm getting there. Here's a screenshot of what I have so far - https://i.imgur.com/bEBIBFF.png. The sequencer, effects rack to the right, keyboard, pad on the left, wave selection, oscilloscope, level meter, master volume and bottom two dial racks (dry/wet levels) are all working. The rest is yet to be plumbed in, but I've added it in to try and get some idea of the final layout.

At present, the sequence of connections for each effect are pre-determined, but I'm working with the idea that a button will flip the synth around so you can patch the units in any order you wish. Another idea is to start with an empty rack and have you add them in and move them around however you wish too, so you could have more than one of each type in the chain. Very much still a work-in-progress!

I'm actually using Tone.js for this project. So far I'm finding it very useful.