First, thanks! It’s a pretty standard greek key design, I can’t really take credit for the squared spirals. I put a .5mm radius on everything, which helps prevent overburn on the inlays, and that’s where I ended up. For more on planar joinery, I have a mega post about it here:
As for dowels, your instincts are dead on. I used the same scheme I did in my previous box in this style:
A head-on view of the layout. You can’t see how it’s fully constructed by there are registration holes that accepted a dowel directly under the magnets and 2 more in the lower corners, making a total of six registration dowels. This kept the BB layers properly aligned for gluing. Six dowels may have been overkill but other boxes I’ve made with two felt like it wasn’t enough. And yes, I cut my dowels to length using the glowforge, of course. Saws are for suckers.