@chromaniac use a case for Note 4G, the ringtone problem will be 50% solved... Further bugs on update is nothing new..
Xiaomi stopped the KK update to RedmiNote_3G due to so many bugs.
But the bugs in
Android 5.0.x is due to
Google itself. Infact lollipop is one hell of an update.. Earlier android updates either take care of UI changes more + slight core OS changes [GB / JB] OR heavy changes in core OS + slight changes in UI [KK].. But wrt Lollipop both areas are having too much tremendous changes
[ART made mandatory, 64 bit OS, Material design, system wide encryption, Project Volta, pop-up notifications, on-screen keys re-design, Complete redesign of drop down notification, to name a few] that even Google struggled to give bug free updates.. Last time such transition was seen in Gingerbread to ICS (for phones) and hence ICS has most slowest adoption rate earlier and NOW that crown was snatched by lollipop..
I think
Motorola is best among others wrt updates [even for mid range phones], even after purchased by
Lenovo. Others incl Lenovo don't give a sh!t about major OS updates, even for flagship phones.. They are like parents who give birth to child and leave them to roam on the road... Atleast you can expect 5.1 in Moto phones that came with 4.2, but for even K3 note that came with 5.0, I can NEVER expect 5.1...
So have patience.. Motorola earlier has released updates faster than older Nexus phones [KK for Moto X OG before Nexus 4]. To continue that trend they have rolled out faster 5.0 updates, not correcting the Google bugs itself. Now they are taking careful steps in releasing 5.1 updates or at least that is what I think. You may remember the 5.0.x bugs in Nexus 5 days..
Let us Say and hope ALL IS WELL...