Periphery outer ring thoughts ?

Two problems. They are a PITA to use and prevent use of an auto lifter.
They have to be heavy to work and this will increase wear on the bearing and motor which has to work harder to get up to speed.
Vacuum hold down is the best followed by reflex clamping as used by Kuzma, SME and Sota. Sota sells a wonderful reflex clamp for much less than a periphery ring. 

My ring is 2.5 pounds; it shouldn't cause problems for a competent bearing.   It works fine even on warped records.  So what if the electric motor works harder to get to speed?

Obviously vacuum hold down will accomplish a similar result.  But it seems that they are complicated and tend to break down.  Reflex clamps are a PITA, more so than a ring IMO.  I used one for many years before the ring.

As for an auto lifter, it may or may not fit.  It would fit on my TT.  But when I want to sleep to music I go digital.

My experience has led me to believe, using my two different tt designs that using an effective mat without a center clamp/weight let's the music becomes free with greater inner detail. Aforeunnoticed small details are heard. Bass sounds full, more real like it does live. 

@billstevenson   I made my own that fits the Technics, a constrained sandwich of stainless steel/acrylic/stainless steel.  It only weighs about 1/2 pound, but it is enough to ensure good contact with my acrylic mat., in combination with the center weight.  It's handy to have access to a CNC shop!

@jbrrp1  Methinks there would be a market for your creation.  I know I would buy one.