I'm all for small keyboards, but I don't know how people do it with fewer than 61 keys. I use fn+HJKL for arrow keys (vim bindings), and fn+number row for F1-F12. Having to use multiple modifiers in common situations like that would be a pain IMO. I've also rebound caps lock to be an additional FN key, but it wouldn't be enough to drop an additional 19 keys I think.