please review:
way/136954695 has the tag
highway=not_path
If this should not be deleted,
what about highway=path + trail_visibility=bad ?

please review:
what is meant with highway=nostop
on node/3029263391 ?
It looks like a highway=noext node,
but highway=nostop seems to indicate that one can go on here? If yes, please add the way.

ja, verstehe ich. Ich würde ja meinen, das
highway=no das schön ausdrückt, aber genau von diesem tag wird mit "do not use" ausdrücklich abgeraten.

interessant. Ich untersuche gerade diverse highway=* tags, die so etwas zum Ausdruck bringen (wollen). Siehe auch
http://gis.19327.n5.nabble.com/how-to-tag-a-quot-highway-quot-that-doesn-t-exist-tt5857111.html
Mir ist noch kein gutes tag eingefallen, das nicht mit einen Life-cycle zu tun hat sondern nur sagen will "mappe hier keinen highway"

Bitte prüfen:
Weg 294501788 hat das sehr ungewöhnliche tag
highway=no_way
In Bing sieht man sehr deutlich einen Weg. Ist Bing nicht mehr aktuell?
Dann wäre wohl highway=dismantled passend, ansonsten evtl. highway=path,
access=private oder so was?

Bitte prüfen:
kann man hier nicht highway=no_path
durch highway=path + trail_visibility=no
(oder horrible) ersetzen? Siehe
trail_visibility=*

please review:
way/320255316 has tag highway=no-track. If you think it should be in OSM,
what do you think about highway=path +
trail_visibility=no ? See
trail_visibility=*

please review:
what does the tag highway=natural
on some nodes mean ? Is it a typo?
nodes: 1697289695,1697289697,1697277217,1697289701

maybe you want to tag the meaning?
I still have no clear idea what the sign looks like, maybe destination=* :
destination=*

sorry, I am not an expert for traffic signs.
This node popped up in my list of unusual highway tags. As I said, traffic_sign=*
is the usual tag.

I found traffc_sign=highway_number is used 4 times, guess that is better,
traffic_sign=road_number would also be new.

please review:
it seems you tried to map some kind of boundary here?
I've changed the relation from
highway=multipolygon to
type=multipolygon, but you have to add
other tags, else both objects are obsolete.

okay, sorry, I did not see that. No idea what traffic_sign that might be :-(

please review:
the tag highway=motorway_signal
is rarely used. Maybe that is a traffic_sign=* ?
If yes, what sign?

please review:
node/288529429 has tag
highway=road_sign
which is rarely used.
I assume you meant traffic_sign=* ?

please review:
the tag highway=red_light
and highway=red_light_camera
are rarely used.
Maybe you find a better tagging here:
osm.wiki/Proposed_features/Relation:enforcement#Example_1:_Simple_Redlight_camera

please review:
the tag highway=rcn_ref on
node/82756308 appears only once in OSM.

please review:
I've changed tag
highway=re to highway=residential
changeset/34771493

please review:
the node/3372859961 is tagged
highway=re
Is that a typo? If not, what does it mean?

please review:
node/271272186 has confusing tags.
Looks like milestone values?
Besides that:
My understanding is that
highway=stop should be used instead of
highway=priority
and the tag should be used on the node
where the traffic has to stop.
highway=stop