Changing Custom Emoji Character Count

Currently, custom emojis take above 20 characters, while normal emojis take only a few, I would like to see a change in how many characters custom emojis would take, maybe by how many characters it takes to type the emoji.

It could count in the ':' on each side or the text in between.
For example:
:love: could be 6 or 4, and :10: could be 4, or 2 characters.