Same here. My only issue with QLandkarteGT is the inability to plan routes.
Again, the old way of doing things would not be going away. This multi-layer stuff would remain compatible with existing styles and scripts. To take advantage of it, you would have to edit the styles and scripts.
I'ld actually rather have the opposite. Get mkgmap to accept multiple input files and merge them into the "same layer". That way one could take 2 osm files, or one 1polish map, one osm, or one .img and one .osm (say one contourlines, one normal map) and join them into one map. Qlandkarte has gone a long way, but still Mapsource draws the maps better looking, quicker and autorouting and generall track planning is much quicker. Also currently Mapsource is needed for sending maps to GPS where you want to have address search. What you're proposing might be appealing to a very small minority, but for 99% of openstreetmap maps in Garmin format, they wouldn't even understand, and furthermore cause loads of support trouble. For it to work nice IMHO the following points would need to be done to Qlandkarte GT before it's really worthwile: 1. Get rid of the stupid yellow points instead of POI symbols (well that is a thing I should write to qlandkarte mailinglist) 2. implement autorouting for garmin .img maps 3. implement a WinGDB like route-/trackpoint adding mechanism so rerouting on GPS is fixed. 4. get a nice GUI to manage layers both for viewing and for selecting what to send to GPS 5. get qlandkarte GT to correctly create the address index for GPS Points 2-5 are all points that Oliver isn't interested in, so it's rather on the people wanting to have multilayered maps to implement it into Qlandkarte GT.