1. Actually we are going to have several functions work on a block of selected drawings in one go. Including adding a clone. This will come soon in one of the alpha releases.
2. You can already now either duplicate a layer, which will keep the clone structure, or select a block of drawings and copy/paste those into another layer. I guess that would do the job?
Moving things along paths is something for compositing as it is right now. But we plan to add this in a future version.