Suggestion: combine existing values and list values in the Tag Panel's fields

It could be written in several topics, so i had rather start a separate topic. I find useful the new solution of the Tag Panel's fields, with the list of user defined values, but i think, the most effective solution would be the following:

<blank>
<keep>
================== (some type of DELIMITER)
value from the selected files field 1
value from the selected files field 2
value from the selected files field 3
==================
value from the custom list 1
value from the custom list 2
value from the custom list 3

Including, of course, even the repetitions of the values of the second and third groups.

And such a solution for genres and all other fields, as well.

Among other things, it would be good to separate the three groups, so that the <blank> and <keep> values are always at the top. I also use parentheses in the case of unknown composers, e.g. (folk song), (gregorian music) to be from the beginning, separate from real names. However, now they also precede the <blank> and <keep> values.

But of course, the main goal is: enjoying the benefits of all three groups.

I do not think, the resource requirement for the computer is significant. But i do not know the extent of the modification of the program.