For the 14" (mine just shipped, yay!) I see four advantages to MagSafe:
- It frees up a Thunderbolt port
- If the charging cord is unexpectedly yanked, the chance of damage is greatly reduced.
- I have USB-C cables attached to chargers everywhere I commonly use my “portable” notebook.
- Less wear and tear on a Thunderbolt port (I’ve never had an issue with it, but some people have expressed concern)
If those things aren’t advantages for you then I don’t see any benefit to MagSafe over USB-C for the 14" MBP.
(I was worried about the return of MagSafe: I’ve really enjoyed being freed from having to use Apple’s (kind of poor) power bricks, and I was absolutely not looking forward to having a cable permanently attached to a brick again, but Apple’s implementation this time around is perfect and addressed all of my fears. Well done Apple!)
ETA: I just realized #3 is a point in favour of USB-C 