Not currently and not in my plans. In addition to work that is needed to make it happen, there are issues with the possible database format changes that would interfere with it. I am sure its possible to do, its just there are different priorities for me (geocoder, for example).

I presume it depends on requirements - whether to keep large regions on device or not. Notice, however, that these days we have two servers distributing the maps. So, if one is down, the second takes over. Since switching to two servers, I don't remember any downtime where the both were unavailable. Which makes it reasonable to consider downloading maps just few days before the trip. But that doesn't help if you have to travel constantly, though