Hi Daniel, thanks for inviting me to the beta tryout for Spirals! I think this will be a cool plugin.
I just tried it and have a few suggestions that I would personally find useful:
1. The size button isn't a consistent delay, is that on purpose? Maybe it would be good to have a delay time knob that gives a consistent delay and then a "chaos" knob that modulates the delay time inconsistently creating the effect I'm hearing atm (which is very cool, but sometimes a consistent delay could be wanted?). That would give a huge amount of extra control I think.
2. Add sync button for the delay time? Change the name from size to delay time or something more intuitive.
3. For the pitch I would like to have the choice (maybe a switch button next to each pitch knob) between the additive pitch and a constant pitch. What you have now is the additive pitch (with each delay the pitch gets shifted more), and the option I'd like to have would be that if I choose a fifth above for example, that it doesn't keep adding another fifth on top with each delay but stays on the pitch of the first fifth. I hope you understand what I mean. Of course that could be done with a normal delay plugin and a pitch shifter in front, but having it added as an option in your plugin would make it easy for example to select a constant pitch in the first delay and an additive pitch in the second delay.
4. I think the size (delay time) reacts differently (faster) when reverse is activated. Here I would also rather have it stay the same with reverse activated or not.
These are just my personal observations/ideas. And I don't know how much work they would mean. All in all it's still a nice tool so far and I'm looking forward to the finished version!