Periphery outer ring thoughts ?

The weight concern to me is more about distribution.  You have to have some clearance built into the engagement interface of your ring (due to the variation in LP outer diameters), and that allows for eccentric placement - - in fact, challenges you to do anything other than place it with some eccentricity (perfection never happens).  With the Technics' powerful DD motor and servo, I have no real fears of it being much affected by an uneven weight distribution.  But with a low-power belt drive TT, I wouldn't rule it out as an issue.
I have encountered enough outer diameter variation that I am contemplating making another ring with a larger clearance to deal with the "super sized" ones.  It's an issue.

There is a balance between the weight (mass) of the platter and the torque of the motor. On some tables adding mass to the platter with worsen wow and flutter. It does not matter how tough your bearing is adding mass will always speed up wear. If you have a suspended turntable it is a total non starter as you upset the balance and tuning of the system. Reflex camps are much easier to use than peripheral rings and press the entire surface of the record into the mat and not just the periphery. Vacuum remains the best. The compressors used are very reliable and quiet. The best system for the money is handily Sota's. 

I do not find a reflex clamp sufficient on its own, as some records don't simply respond flat.  Just tap them and you can hear the "play" and opportunity for vibration mischief.  I would agree that a well executed vacuum system is ideal.  It's too bad my SOTA Cosmos didn't sound as good as my new Technics...

@jbrrp1 

My clamp is a 2.5 lb sandwich of plated copper with a sliver of some sort of soft plastic in between.  It sits about .01" above the disk.  Made by TTWeights, it was NOS when I bought it about 7 years ago and was an old and discontinued model at the time the company closed.  It is always centered perfectly about the spindle and has worked without a problem for a large variety of recordings over the many years.  I use it with a simple center weight.  Both the ring and the weight go on faster than the VPI screw ever did.

I have never seen a reason for mounting it with any eccentricity at all, and have never seen a record with which it does not work perfectly,  Perhaps you might want to revisit your design.