Cheek weld should not be a real concern when using a red dot optic, if you are using the red dot correctly. It is not important as to where the red dot is in relationship to the optical field, only that it is placed on target. A good example is the Russian PK-AS red dot sight. The low, offset version mounts completely left of the centerline of the barrel (probably a good inch or more to the left of the barrel). The high, in-line version mounts probably 2" or more above the receiver. But both sights work flawlessly when once you remember that a red dot sight is designed to be used with both eyes open and a “heads up” stance.
Standard offset version of PK-AS on the left - High mounted, centered version on the right.
My wife's RRA 9mm carbine with a Burris XTS-135 mounted on the A2 upper.