Add a filter list similar to what we have in Glyphs for isolating categories or scripts.
When copying an entire entry from the master GlyphData.xml file (I use TextMate for that) I can see that it would be useful if I could paste the copied entry into a data field and have it auto-fill all the appropriate fields. Perhaps a “Copy” field which would then auto-fill all the data. Alternatively, allow copying directly from another GlyphData.xml file.
I suspect Merge would bring in the entire file. I don’t need the whole thing, but very often I do want to copy a single line to modify it for a specific font.
Indeed one can merge individual entries, but a minimum of a Unicode value must be known and added before any Merge can happen.
I wonder how this will work with unencoded characters because then one would need to know a name. In such a case it would be faster to do the job with [the text editor of your choice].