I’ve been doing some work on cycle routes around Thun, and would also like to work on the local hiking routes.
For the national and regional routes, I think we should consider splitting the relations into sub-relations, each corresponding to a stage/etappe on the wanderland.ch website. Each route has its own parent relation that has each stage’s relation as a child member.
I wouldn’t care too much about the stages proposed by Swissmobile. It is not something that is really part of the route (and only indirectly signed, so no on-the-ground-information), If you find the routes hard to handle, just split them at a point where it makes sense. In any case, I would create relations that are much longer than the stages proposed by Swissmobile, otherwise you end up with too many sub-relations. Splitting regional relations is most probably not worth it, I have not yet seen any that is longer than 100km.