Schafer should have better plate discipline and a little more power than Jones. Jones' plate discipline to date has been what is holding him back- maybe this year Jones will start to overcome that.
Schafer is young and raw and will probably have his ups and downs. But if Schafer gets enough PT, I think you will get a little better hitting numbers (AVG, OPS, R, RBIs) from Schafer than Jones but Jones should beat him out in steals. As it stands now, I think Jones will see a lot more action while Schafer may be eased into things via a platoon.
If Schafer gets enough PT, I think you will see numbers like Joey Votto last year but with a few more steals and a few less RBIs.