Cooker hob might be a problem I guess - don't know a lot about options there. Lower units/work surface obviously - but I'm sure you've thought of that. Also lower sockets. I'm sure neither of those present much of a problem.
Maybe have a staggered worktop size since lower height of these might be problem for you or other taller people to use?
Most storage in floor level presses rather than up on shelves or high presses.
Side by side fridge and freezer
Switch for extractor fan on counter rather than on extractor
Retractable step set in to kick-boards