Http doesn't have that much overhead (especially when you want to send things in the MB range)

What kinds of applications are you talking about? Are you thinking TCP/IP connectivity or something slower?

You can build a network mesh out of wireless point to point and 802.11s mesh networks. It is all TCP/IP networking so you can run any application you want over it.

https://en.wikipedia.org/wiki/Babel_(protocol)

https://www.open-mesh.org/projects/batman-adv/wiki/Wiki

Edit:

I forgot about HaLow. It is lower bandwidth but it has a much longer range. https://en.wikipedia.org/wiki/IEEE_802.11ah