I have top of the line late-2013 model, i7 with 1T SSD and 16G RAM. There was no reason to upgrade whatsoever so far, and current MacBooks are not appealing to me at all. Mostly I would like them to return good things back and introduce new things they implemented in other products.

Absolutely NO WAY to the Touch Bar. As long as it's there, I'm not even looking further. It can have 512GB RAM or all-gold unibody or whatever, Touch Bar = no buy.

One thing I use extensively is the Toslink digital out, I love music and being able to connect portable DACs over Toslink is (was) beautiful.

I'm sure the sound system could be improved. It's nice to watch a movie in bed sometimes, but the sound is bad on 2013 model and somehow even worse (very synthetic?) on 2017.

It would be nice to have a screen that doesn't have all your keyboard imprinted all over it in a year or so.

A way to disable Apple logo glowing.

32G RAM goes without saying. I'm a developer and even without 1-2 VMs I sometimes run out of memory.

To conclude, we need faster horses, Mr Ford.