First of all, I edited your query to remove your email address so that you do not receive a ton of SPAM as a result (it may already be too late; time will tell). People can respond to your query here and you will get notification of their responses being posted.
I can think of two ways that you could connect a 10Gb Ethernet controller to this NUC with the expectation of getting its full performance.
- Install a M.2 card that brings out the x4 PCIe lanes from the M.2 connector and exposes them in a x4, x8 or x16 PCIe card connector. A PCIe board with 10Gb Ethernet controller could then be plugged into this connector.
- Use a Thunderbolt adapter that exposes a 10Gb Ethernet controller on the Thunderbolt3 bus.
Hope this helps,