See http://forum.tp-link.com/showthread.php?99025-How-to-configure-Multiple-SSIDs-with-Multiple-VLANs-on-CAP-amp-AC-products for a How-To. Even if you don't use the devices mentioned there, it will...

If you have fiber, I would recommend Pharos CPEs (CPE510 or WBS510 with external antenna), which are the successors of TL-WA7x10. See http://www.tp-link.com/us/products/details/cat-37_CPE510.html

From the download page: Bug fixes: Modify transmission power per region to compliant with regional regulations. If you did download the firmware for your region, it now complies with the legal...

The AC50 is neither a switch nor a router. For IP forwarding / NATing you need a router.

RTouris wrote i.e. ~12.5MB/s (100mbps) Correct, but if true full-duplex is enabled, it yields ~22 to 24 MB/s at 200 Mbps (100BASE-TX allows FD mode with simultaneous sender/receiver @ 100 Mbit/s...

Just search the forum, it's all there: http://forum.tp-link.com/showthread.php?99025-How-to-configure-Multiple-SSIDs-with-Multiple-VLANs-on-CAP-amp-AC-products If your router supports 802.1q VLANs,...