[spantaleev]

For something that can help make Nagios management easier, you could use something like nagadmin: https://github.com/devture/nagadmin

It's both a web-configurator and a replacement for the default interface - no need to learn much about Nagios (unless you want to) and should be satisfactory for a simple use-case. Certainly not a replacement for the more complicated and scalable configuration/frontend solutions out there, but it does serve its purpose.

[jorts]

Opsview, Icinga, Groundworks, Nagios XI, etc... also put a decent UI on top of Nagios Core.