One space that I don't think I've seen explored is building a laptop around a tiny, ultra-low-power passively cooled SoC board that can easily fit
beside the keyboard instead of
under it in a 12"-16" chassis and saves space that'd otherwise need to be dedicated to cooling. That'd buy a substantial amount of Z-budget for a quality keyboard without blowing up chassis thickness.
Naturally this laptop wouldn't be suited for some types of work due to lack of horsepower, but there's always tradeoffs somewhere.
