Thanks for your answer.

As usual, there can be no exact boundries drawn. There are however a few aspects to weight together to decide whether a path should be drawn separately or tagged on the main road. I can't seem to find a wiki page dedicated to where to draw the line, so the following are my mapping practices, and judgments after lots of community consultation on several edge-cases I've stumbled upon over the years.

One aspect is distance. If there is so much space that grass is grown as separation, how would you map the grass if the ways were not separately mapped? Here, the mapping aspect decides for us. If people usually cross the grass at a certain point, an "informal path" can be drawn over the grass, but usually, people walk along the footway and don't cross the grass if it's not in the way.

Another aspect is physical barriers, and a high kerb is often considered too much of a barrier for the ways not to be mapped separately. It's impossible to traverse with a wheelchair, scooter, sportscar etc. Possible with a bike or a normal car with great care, but not advisable, and sometimes illegal. You would not connect a road or a bike path over a high kerb, but a non-wheelchair friendly "footway link" could cross such a kerb.

For separation between a parallel footway and cycleway:
- A high kerb with street light posts inbetween makes the footway more of a "sidewalk" to the cycleway, so separated ways felt natural there, but some considered it too detailed, although an acceptable way of mapping. 
- Just a painted line obviously doesn't warrant separated mapping, as there is no physical separation at all. 
- A slanted kerb is an edgecase, where I believe a majority of people would lean to mapping as a combined cycle- and foot path, as you can easily traverse it with a bike, and with some difficulty probably also with a wheelchair. 
- Having no height difference at all, and only a change of surfaces, as is the case we're discussing here, is considered no physical separation. You wouldn't map sidewalks on a pedestrian street where the middle section is sett and the edges paving stones, and you wouldn't map separated paths here either, where the cycleway and footway run parallel to each other with no obstacles in between. 

If there are planters, bike parking or benches etc, as is the case on the corner of Thulegatan and Råsundavägen, for example, separated paths should be drawn (and I missed those). But here it's also up to the mapper to judge how many crossing ways are needed between two separate paths (since they inhibit routing between them if there are no connecting paths). If there is no navigational need to cross between say two benches placed a few metres apart, even though physically possible, a separate footway would be unnecessary clutter. But if there is an entrance at that point, a crossing footway would be beneficial, to facilitate routing up to the entrance from the bike path.

I hope this gives you insight into my reasoning and makes sense!