I'm on a late 2013 15" MBP and I am dreading the day when I need to replace this joy of a machine.
I like the idea of the touch bar, but I don't actually want it for keys. I think it'd be handy as a ticker for notifications, macros, etc, but not common keys.
Having a bar for macros / shortcut keys for Illustrator (etc) would be extremely useful for designers, and I don't doubt that there are hundreds of other applications for other industries. Sort of like those LED keyboards that were kicking around a few years back.
The requirement for dongles is just silly. I actually purchased this late-2013 MBP refurbished specifically because I didn't like the new GPU and read some other complaints about the current systems of the day. Having an SD slot, HDMI, 2x USB, etc is excellent and can easily handle most of my needs when I'm on-the-go. At home I have my laptop on a VESA mounted tray with a second monitor.
All in all, there isn't a lot that Apple needs to improve with the MBP -- they just need to dial it back a few generations and retool the touchbar so its not mandatory.
Lastly, bring back magsafe! Maybe there are some people who hated it, but I've never had any issues with it. There have been a few times where the cable has been kicked (often at a coffee shop by someone else.) Its a fantastic design, even if the magnets could be the tiniest bit stronger.
quick edit: I hope things don't go the way of using the camera for quick unlocking. I always keep my cameras covered, even if makes me look like I'm paranoid. Using touch ID on the touch bar would definitely be ideal.