Is my Netgear WAX202 a bottleneck?

I'm glad that worked for you!

(Here's more info on why it works: https://en.wikipedia.org/wiki/TCP_offload_engine - it works for more than UDP, just the name of the Wiki and what it was first designed for. The WAX202 has capable hardware.)

BTW, the current version of OpenWrt is available for your device.

If your problem is solved, please consider marking this topic as [Solved]. See How to mark a topic as [Solved] for a short how-to.