Hi again,
Thanks for giving this some thought!

I've also been wondering whether node or way was better... I think both could be used depending on the circumstances: Way for spurs significantly longer than wide, but node for roundish spurs having width~length.

In orienteering (the sport) it is a must that any feature (a spur in this case) used for a control can be located to within a ~5m radius, and the default location for an orienteering control on a spur is "on top" of the spur. Thus I have a clear intuition that node is ok, and I implicitly assume the "on top" location to be the thing to map. I cannot think of a better part of the spur to map, but open to input! "On top" coincidentally matches the locations of the two viewpoint at hand (but that is of course not in itself a reason for "on top" being the generally understood interpretation of spur...)

Thanks for suggesting natural=ridge. It is a very related concept, and maybe there are cases where both could apply. Yet it is my understanding that a ridge is not (always) the same as a spur. Here are some ways in which I think the two differ:
- A spur is smaller than a ridge
- A spur protrudes from a hillside/slope, whereas a ridge is more of its own feature (probably connected to the first item about size)
- A ridge has a "continuous elevated crest"[1], whereas a spur is always sloping downwards ([4] seems to not agree to this, and have both slope downwards...)
- We have language for both, indicating that separate concepts are meaningful and useful for e.g. navigators. Examples of separate use in [2], [3], [4]

[1] https://wiki.openstreetmap.org/wiki/Tag:natural=ridge
[2] https://askaboutireland.ie/learning-zone/primary-students/5th-+-6th-class/geography/maps-and-map-reading/landscape-features/valleys-ridges-and-spurs/
[3] https://www.armystudyguide.com/content/Prep_For_Basic_Training/Prep_for_basic_land_navigation/spur-minor-terrain-featur.shtml
[4] https://www.bushwalking101.org/interpreting-map-features/