Save and use a custom character set

I use Character Map (charmap) but I find it annoying to search through all the characters for the ones I want, because I only use about 30 of them regularly.

What I want to do is add characters that I use often to use to a custom "script" that would ideally appear in the character map sidebar as shown, as for example "my charset"

However, it would be perfectly fine for this favourite character set to be available from some other interface, (it doesn't have to be graphical) as long as it displays the characters so I don't have to try to remember all the unicode numbers :)