I’m a CLI guy and I feel disoriented if I cannot ssh a server 
I even try to put an sshd on Windows machine from time to time… Still, we chose NethServer in a project where non-technical people was involved because of its clean and simple web GUI.
NethServer has some minor issues to cover up with its web interface (for example, an interface to manage joined clients, allowing to remove them/renaming them if possible), but a massive work has already been put in place to make 95% of the things you are required to do manageable within its webgui.
I’m pretty confident its community and its developers will cope with the needs sooner or later. Plus, they developed an MVC framework with PHP, so it should be quite simple to implement some newer interfaces. We have done it and will be doing it again soon 
Of course, we checked out Zentyal and ClearOS before, only to discard them because they are mainly enterprise-focused and we required a free license+no costs for the customer. They weren’t anyways as complete as NethServer, thanks to its e-smith+templating layer.
I will continue to call db/signal-event commands on the CLI, even if there will be a mobile app to customize your NethServer, granted