Salve,
thanks for the feedback. I still see some residential roads like Via Monte Grappa or Via Professor Oliva which are tagged unclassified. Maybe you can clean up those as well?

Hi!
Please check:
I corrected typo highway=residental
on some ways. Watch out when JOSM
auto complete suggests this again ;-)
See changeset/51662618

Hi!
Wouldn't it be better to use the normal tagging highway=proposed and add other tags to separate the alternatives, maybe note="alternative xyz" ?

Hi!
Please review all ways in this area. I see typo highway=pprop on way/463545841 and combination highway=proposed + construction=*
I don't know which one is correct.

Hi!
I've noticed this change because you used the very unusual highway=nonexistent.
Please check osm.wiki/Lifecycle_prefix

I will. Thanks for the positive feedback :-)

Hi!
Please review typo highway=ford on
way/259801871
Did you mean ford=yes?
See also ford=*

Hi!
Please check typo highway=farmland
on way/518737011
Not sure what that is, looks like a path next to a barrier?

I use the data from taginfo to find untypical values for the highway key:
https://taginfo.openstreetmap.org/keys/highway#values
Next I use the Overpass API to download the objects. When I see that many
of them were created by the same mapper I contact them.
I also started to open tickets in JOSM, without much success so far, see
https://josm.openstreetmap.de/ticket/15203#comment:13 and below.

Please check also way/520288439
track or path?

That's new to me. I don't find that tag in the wiki or in JOSM presets. Where do you find it? Taginfo shows only 7 uses, so I think that editor should be corrected.

Falls es noch nicht klar ist: Mir geht es nur um diese Fläche:
way/333038647

Hallo Tutilo,
was willst Du denn mit highway=chess beschreiben?
Gerd

Moin!
Was bedeutet denn highway=emergency_access_point
an diesem Weg:
way/501704665
Ist das ein Fluchtweg oder so was?
Siehe auch highway=emergency_access_point

Please review:
You have accidentially changed some highway=residential to highway=emergency_access_point:
http://overpass-turbo.eu/s/rp5

I've tried to fix mapping of
way/487482051
See changeset/51643049

Warum dann nicht highway=service anstelle des seltsamen highway=chess?
Tippfehler?

I cannot speak for the community. I'd prefer the other mapping method as it is less likely to break pedestrian routing. A missing sidewalk tag on a highway=residential is rather harmiess compared to a missing connection between all the highway=footway ways.

Hi!
Please review. I'd prefer
disused:highway=cycleway.
See osm.wiki/Lifecycle_prefix
You did not change the route relation
relation/272134
I assume the closed ways should be removed?

Since there are so many relations you may also just change it to highway=service + access=no + psv=yes if that is apropriate.