I have installed mwan3 and created a basic configuration that reflects my router / wan configuration. The LuCi extensions developed by the mwan3 team (primarily Network / Load Balancing) are not included in the default LuCi as installed on my Omnia. There are, however, features that appear to have been added by the Omnia team (LED color control, which is useful to distinguish WAN from LAN, for esxample). I have not yet installed the mwan3 version of LuCi out of concern that I will lose the Omnia-supplied features. Is this concern valid, or does the mwan3 LuCi only add extensions?
Resolved, but for the benefit of others the answer is that installing package luci-app-mwan3 adds menu items under Status and Network, without interfering with any Omnia-provided menu items / features. Also it adds GREAT tools for managing and configuring.