There are products you can use to modify some characteristics of printing ink, also (I imagine you know this better than I do - I’m typing it out for folks who don’t know this stuff) which are primarily used by the letterpress crowd in order to tune working times and thin film characteristics.
The cobalt (and other metal-ion) driers do work really well, though as you note it changes the PPE concerns somewhat.
Your expandable grid board is AWESOME. Like truly remarkable! In your place I would be thinking more along the lines of a letterpress chase, which would necessarily require a different one for each size, rather than this really ingenious modular set!
Really brilliant.