All my video and photo gear use Manfrotto quick release adapters and 501 PL plates. I have various fluid heads and slider mounts. My Ronin-M is accepting the 501 PL plate as well.
This solution works great in most cases but has one significant shortcoming – it's not very convenient with smaller cameras (like Sony A7R or Panasonic GH4 etc). The plate is quite long and sticks out especially when the camera is not mounted.

I found the solution to this inconvenience quite a long time ago and thought that maybe some of you could benefit from that.
Back in my 5D days, I was using Kamerar QV-1 Viewfinder as a loupe to help me focus in the bright sunlight.

The interesting part is that the viewfinder comes with a custom made plate which is compatible with Manfrotto 501 PL plate!
On top of that it has a few advantages:
- It's much smaller – works better with cameras like Sony A7R, GH4, etc.
- Works both ways (you can mount it from both directions whereas the original plate can be mounted only in one direction).
- 1/4" & 3/8" threads at the bottom

Even though I don't use the viewfinder anymore I ordered a few plates and have them on my smaller cameras all the time.

This way I use one type of quick release adapters and original plates for bigger and heavier cameras, and QV-1 from Kamerar for smaller ones.