Hello, thanks for all the support and feedback!
The custom library support will be enabled very soon, right after the reworked male template is completed. In the nightly version, when browsing clothing/hair templates, you can already see a drop-down menu in the top left corner of the library window; and in the Preferences tab, the functionality to add/edit the list of folders to scan for custom libraries are already functioning. Just a little bit more, we also can't wait for it to be finished!
As for the Ctrl+Mousewheel, it sounds simple enough and we can't see any problem with it except maybe the rendering performance. Let's see if we can add the functionality around this weekend.
Again, thank you very much for you support and suggestion, and hopefully the app will be more useful to you as it grows!