I definitely think some improvements can be made to the HHKB layout. The only thing I think would NEED to stay is the backspace position..which is far superior...
If you added another key and used capslock as FN instead of CTRL, that's not a bad choice.and it would free up the easy use of IJKL as arrow keys like with the Poker 3..great way to use that space...barely need to move your hands to use arrow keys now..I think that is great...Some people like the gap in the HHKB layout where it is missing keys...I dunno..looks like...but I'm ok with improvements to the FN layer and utilizing that space...
But it still remains, if you need to use the FN layer a ton, 60%s are just not great for that...for most people they don't so it works out but if they did, it would suck...
So for me, a combination of the Poker 3 + HHKB Backspace position is ideal for me...now, what to do about keycaps...