I'm sorry if this had been talk about before.
I mainly using Offline Maps(personal) from Google Maps.
But many time it can be inconvenience to switch between Online and Personal when some parts of the maps are not covered in the offline files.
I think it would be nice if the Online and Personal maps can work together.
If the tiles exist in offline files Locus use the offline data, if the tiles are not exist in offline files Locus will look in Online file, and if the tiles are not exist in Online file too Locus will download those tiles and store in Online file.