Just yesterday I thought about the vice versa way... Wouldn't it be nice if one could bisect the nix configuration. Well technical you can already dealing with git, but a 'nixos-rebuild bisect' would be a nice shortcut. Esp. for config problems which aren't identified immediately. One of those "whoa, since when did my exotic seldomly used hardware stop to work..."-moments.
Not asking much... Just if they just would add a trackpoint, a decent mechanical keyboard (don't mind if this adds 0.5cm to the thickness) and offer a black chassis... I feel they would really be the new home of former IBM ThinkPad users which are more and more disappointed about Lenovos decisions to try to compete with Macs.