Mesh network setup

I have a dozen of dual band routers running openwrt 19.07.
I created a batman-adv mesh following the tutorial provided by openwrt.
I wanted to know is it a good idea to use 5ghz band only for mesh backhaul and access point only on 2.4ghz where clients can connect to the network ,if not what is the best way to setup the mesh ?
(extra note : client devices supports both 2.4 and 5 ghz bands)

I would definitely recommend to use both of the frequencies for both of the uses (mesh and end user devices).
I would definitely recommend using for this, as it is already implemented.