Recently bought these not even 30 days ago; and the fact that these devices are missing security features that are in older mesh networks/routers is baffling. 

No Device MAC White List.  I've had other routers where it is possible to get approval before a device can join your network or its simply blocked. Not here.

Blacklist Websites at the Router/AP level. Can see this can be done from the profiles, but not from a 'higher level.' Even routers from 10 years ago, have this option. 

No Website Whitelist. Maybe I want it to where one device or profile can only access the websites that I want. Not Possible.

Splitting the 2.4ghz and 5ghz channels. Maybe this is possible, maybe it isn't - couldn't find out how.

Disabling DHCP server and NAT in router operation mode  - Everyone's setup is different - so it would be nice as a option.

Now if these are available, maybe someone can point it out and not have the interface so ambiguous, but if it isn't available - as you do with other posts - please "send to the R&D team" ....