Hi Mesata,

You're right that the tagging over here is terribly inconsistent, we're slowly working on this :)
There is almost nothing on OSM wiki on Armenia, however there is a weak consensus in Russian-speaking community that smaller ways within urban blocks should be tagged as highway=service & living_street=yes. It's in Russian but auto-translatable: https://wiki.openstreetmap.org/wiki/RU:Россия/Голосования/Дворы and 
https://wiki.openstreetmap.org/wiki/RU:Highway_classification#Классификация_дорог_внутри_населенных_пунктов
We've took the liberty to use this convention in Armenia due to similarities in post-Soviet city planning

On your examples:
 - https://www.openstreetmap.org/way/173489561 - this does look like a street, I'd leave it as residential for the time being. It might have a name as well, we just don't know it (yet). I'll try to find more info on it. There are a lot of unnamed residential ways in Armenia - this approach is correct if a way is in fact a street, with houses lined along it etc. but there is no info on the name. This especially is the case with smaller towns and villages. Living streets around it are plain wrong though, highway=living_street should only be mapped on ways where pedestrians have legal priority with road signs like this: https://en.wikipedia.org/wiki/Living_street#/media/File:RU_road_sign_5.21.svg, and we're yet to find one in Armenia. However not all mappers agree - a lot of residential and service ways here are mapped as living streets.

- https://www.openstreetmap.org/way/449256583 - if the street name tag is correct, the service tag is a mistake. I'll try to check this place in person, if this is in fact a named street, it should be residential.

- I'll try to survey the way in question to check whether it looks more like a street or just a way within the block.

Thanks for your work and a great day to you too!