I would like to import and export more than one microflow without importing / exporting a whole module. I also would like to import / export folders and subfolders (and maintaining the tree structure) which contain microflows. Does anyone know if it is possible to do so?
No, that's currently not supported. You have to export one for one, or export the module. If it's important for you, you can add a feature request in mxdn.
Another nice functionality would be moving folders which contain microflows from one module to another within the same project.
In 2.4 the tree structure is maintained when exporting and then importing (individual) microflows/forms.