What about adding motorways? OSM indicates routes with M prefix. Dunno if they are signed.
The M routes are metropolitan routes, a minority of which are motorways. South Africa signs motorway status with blue signs (instead of green), not with a particular alphanumeric route designation. Si404 has already drafted zaff, which will add a lot of freeways/motorways not already in zafn or zafr.
Metropolitan routes are signed (in theory). In peer reviewing zafr, I noticed Capetown signs most M routes quite well, and Johannesburg maybe used to sign its system well, but most of the signs have vanished. The other cities with M routes seem to lie somewhere in the middle. I have yet to find any official lists of M routes, but Wikipedia has detailed route descriptions for Johannesburg, as well as summarized route descriptions for East London/Buffalo City, Capetown, Pretoria/Tshwane, Durban/Ethekwini, Bloemfontein/Mangaung, Port Elizabeth/Gqeberha, and Pietermaritzburg. I also stumbled across small metropolitan route systems in Welkom and in Vereeniging and Vanderbijlpark, which are not documented at all on Wikipedia. It's quite possible that there are other systems that I am unaware of.
In theory, I think adding metropolitan routes would be worthwhile, since most large cities (excluding Johannesburg) don't have a lot of R routes in the urban and suburban areas. In practice, drafting some systems would be quite difficult. Signage is often deficient, and in some cases is even contradictory. (See my confusion over the correct route of East London's M18 above.) I also don't know the extent to which the Wikipedia lists are complete. For example,
M20 is missing from the list of East London's M routes.
What about 3-digit R routes e.g. Cape Town's outer beltway R300?
This is the logical next step if we want to add more routes in South Africa (which I think we should, since the routes we currently have mapped are quite sparse compared to the average U.S. state or European country). Wikipedia lists 230 regional routes. If we mapped them, we would get a slightly different number for three reasons:
1. The R100s are old alignments of national routes, and therefore most are split into multiple discontinuous segments that we would have to draft as separate routes.
2. At least several are unsigned and have been for well over a decade, despite appearing in the RDDA (such as R724).
3. Wikipedia is missing at least one route (R373).
Unfortunately, the RDDA isn't a trustworthy source for all of the regional routes because it is outdated. I came across numerous examples where a regional route had been decommissioned, and the number had quickly been reassigned to a new route in a completely different location.
