For switches I used all of the random switches I had from a couple of switch testers I already owned. My only thought when picking switches was not placing similar switches close together and I did not want clicky switches, but one of them sneaked in.Wiring and programming were exactly the same as the macro pad, just more of it. I did not give myself enough extra wire to route it well inside the case which caused the first case I printed not to fit, so I made the case taller and printed it again. That one fit everything but the keyboard only worked intermittently. After a lot of frustration, I realized the reset button on the Arduino was being depressed by the case. A little bit of Dremel tool work later and the keyboard now works great.
I spent an hour or so typing on it and realized that I don’t like ortholinear layout so much. I think it is something I could learn, but then it would be harder to type on standard keyboards, I have a hard time making mental shifts like that. But if I could get a 75% keyboard with a split spacebar and 1u keys on the bottom row… I would jump at that. I may have to build that myself at some point.
I have decided that building the Planck was a great experience and it is a fun conversation piece, but not something I would regularly use.