That 3/8-24 hole in the middle of the plate provides good clearance for most of my through drill work but it can be problematic when working with very small parts. The solution was to make a threaded plug for the hole that sits flush with the top of the table when inserted. It projects a bit on the bottom so it can be locked in place with a 3/8-24 nut.

I could make a threaded stud to go in that hole and thus have an omnidirectional clamping capability for larger parts but so far I've had no need of it. However, keep the idea in mind if you decide to make something similar. Such an arrangement would make it very similar to the classic British design of a finger plate.