No, I didn't experiment with modes almost at all. I had one mode where I mapped the arrows to individual keys but in the end dint't use it - it's faster to enter a chord - especially chords for Ctrl+Arrows are nice.
For a time I made the mappings a little more memorable by forcing two related keys (like a and ą or o and ó) to have their chords differ in just one finger position - and that did work but it lowered the "efficiency estamates" of the generated layouts. In the end I reserved one thumb position for my custom shortcuts and allowed the optimizer to go crazy with all the remaining chords. After playing with both styles I prefer the latter. Entering text feels more a little fast-paced maze solving game where you have to figure out which fingers to move to transition between chords.
For a time I made the mappings a little more memorable by forcing two related keys (like a and ą or o and ó) to have their chords differ in just one finger position - and that did work but it lowered the "efficiency estamates" of the generated layouts. In the end I reserved one thumb position for my custom shortcuts and allowed the optimizer to go crazy with all the remaining chords. After playing with both styles I prefer the latter. Entering text feels more a little fast-paced maze solving game where you have to figure out which fingers to move to transition between chords.