Hello, welcome! Thanks for your feedback.
First of all let me point you to the blog, where we discuss future directions, we discuss your suggestions, we consider pros and cons of features. (But I see you have discovered it already).
* more drag&drop is planned.
* portability: Tabbles already works with removable devices, such as usb sticks. It even watches for moved files on the drives and updates tabbles accordingly. What else do you need?
* combine link and unlink to tabbles. Good idea. Notice this is only possible when you have selected one file. (if you have selected two files which have different tabbles, I wouldn’t know how to fill the dialog). It was already in the TODO, but with low priority. I’m increasing it.
* being able to reanme tabbles in the quick-open dialog? Maybe by right-clicking? Yes, that would be useful. I am adding it to the todo list.
* Custom category arrangement: I see you have read the blog and installed the new version, so you know there are no categories anymore. The reasons are explained in this blog post. 🙂