You do know it's quite difficult to make a point-to-point link with most Part 15 equipment unless it was manufactured for that purpose. Since Amateurs may modify equipment and antennas, it's actually the Part 15 user who has the constraint. Part 15 users must buy (often more expensive) equipment that was made specifically for point-to-point, high power, directional and/or high gain connections; and may not modify it in any way. I think you're using the phrase "Mesh" in the in definition of multiple interconnected points (which is by definition is a many/one-to-many LINKING); but it's also a routing protocol...meaning that a point-to-point (one-to-one link) can be used to interconnect two islands of Mesh nodes (e.g. across hilly terrain) by simply establishing a signal link and setting the channel and SSID. And, with no further configuration necessary, two islands of Mesh nodes instantly can reach one another. Also, please elaborate on the "constraints" you envision with using an Amateur-based Mesh Network.