Navigation design: we will probably get some help also from the designer of several L5 mockups. I think @pichlo is on the right track and we will all try to make the UI as good as we can. @pichlo, with the configuration - we probably have to agree on what to put where and then see what to configure.

Desktop: icons are huge, indeed. I filed the issue regarding it. I am planning to tune desktop, but probably not immediately. There are few issues that I'd like to fix first and also push OSM Scout Server instructions (maybe also flatpak) for desktop. So, the users could immediately use it in offline mode. Also, I have to add support for entering personal API keys - otherwise we risk running over limits. Just have to be ready for it. Then we should be able to start pushing desktop versions more.

Re desktop routing - should be on the same spot as usual. Just catching GPS is tricky without it. Hence its probably a thinnish bar on top.

Re flatpak: as a user, I agree, its always better to install repo's version. as a dev, I can see advantages now. Although, as a dev, its not too rosy either.