A 6D Mark 1 would be a nice upgrade to full-frame. You can get one used for < 1,000 and have lots of money to spare. All the great deals on new Canon ended with the holidays.
Full frame is way better than cropped censor when it comes to lenses. With the 6D II you will be able to take a full advantage of the pro line of the EF lens line up and the focal length is exactly what is should be. A beginner should appreciate the "extra" possibly and nobs which only available to pro as they grow. Go with the 6D II
jrqaDO.