The road alignments here prior to your changeset were up-to-date. The new alignments are more visible in the Esri imagery which is dated Feb 22, 2025.

The correct tag for any sort of community within a larger community would be neighborhood, quarter, or suburb. "Community" is also a very vague word and thus would not make a good tag in OSM. You could essentially say that it already does exist in the form of most place=* tags, be it a neighborhood, hamlet, village, city, suburb, etc. Also worth noting that Wikipedia descriptions don't match 1:1 with OSMs definitions, and the word "community" is used in the context of Sumnerlin being a master-planned community rather than the word alone being used to indicate what specific type of populated place it is.

Summerlin South is technically separate from Summerlin proper as it is a CDP in unincorporated Clark County, while the original Summerlin development is inside of the Las Vegas city limits. Even if Summerlin encompassed areas outside of the city limits, it should not be tagged as a town as it is not a entirely separate from Las Vegas as an unincorporated community or a separate legal entity.

C/D lanes are still links in the scope of OSM but are significantly different from regular ramps/slip lanes.

For example, the ramps between Sky Pointe and Oso Blanca serve more as surface streets/frontage roads as they pass through signalized intersections and aren't exclusively for entering the freeway. Same for the Ann/Rancho ramps.

The C/D lanes are more complex and are considerably more a part of the freeway than the aforementioned ramps which divert and connect directly to surface streets via signalized intersections. They parallel the mainline carriageways and link them to multiple exits. Surface road traffic is expected to use them when travelling a short distance down to the next exit or so, essentially making them a component of the freeway rather than lengthy unnamed ramps between surface streets. This is especially apparent at the Spaghetti Bowl, where the C/D lanes are so long and convoluted they can't be just be chalked down to a slip way between MLK and Charleston when the ramp is mostly serving traffic making the 95 S/15 S movement.

As for St. Rose Pkwy, this road cuts a larger route than Rancho does (which only meets the same highway that it diverts off of). It also has a higher capacity, speed limit, and access control to compensate, and while these attributes in their own right don't dictate the classification of a road, they do amount to how traffic uses or could use the road, which is as a link between Henderson/I 215 and I 15.

Considering this is the 95 Business route, that would make US 95/Oran K. Gragson Fwy the official bypass. Rancho should remain primary since its role is only to be an urban arterial road and not a thruway for long distance traffic. I would also keep the collector/distributor lanes paralleling the freeways as motorway links, especially since part of these ramps are the direct link between 95 S and 15 S, and the rest link too many different roads to the freeway for its main purpose to be a link between two surface roads.