1st step: don't post on proven nazi sites.

I don't know how it is in the UK, but I use street complete to contribute to osm

No repo yet but I'm actually working on an app for contributing POIs that's like everydoor but just meant to be much easier to use. I actually hope everydoor would take some of the design choices one day when they get funding to continue work. For now they don't seem to be accepting PRs.

Neat ... the public transport issue is unfortunately a big one, and the hardest to solve :(

Not just the live updates and departure/arrival times, but starting with the sheer existence. In the (reasonably big) city where I live the only thing to be found in OSM/CoMaps/OrganicMaps is the subway.

No buses (including nightbuses for when the subway doesn't run), no commuter rail for the surrounding cities and suburbs, no tram ...

Not sure where this data could be accessed ...

EDIT: Now that I'm looking at it again, it seems that at least some bus lines are available in OrganicMaps, but you have to look for a stop, click on the line, and it will show you the route. It's not integrated with the route lookup feature though :(