I can see why you are retired Sophie, your arrogance is noted. Your invalid assumptions and snipey tone suggest it may be time to take up knitting or at least find another forum? We have several professionals involved on this high end project. All of whom understand ergonomics. Nevertheless, I was interested in other opinions as there is still an acceptable range within expert views and average heights are on the rise. That said, from a stylistic point of view there is often a push toward lower. Further, the huge range of heights in ready made furniture shows just how much variation there is. Some of it is ergonomically designed, some is not.

I hope you guys covered the ceiling.

Depends on which room it is! If you're spending a lot of time in there, a lighter colour is best because with warmer colours, it tends to bring down the roof a bit if that makes sense - what did you end up doing?

I'm thinking you should make them higher as the ceiling goes higher, but that's just my opinion. It's a slight difference in height between the exterior sliding doors but the height difference will be good I think. What'd you end up doing?