In this update, you can change values of different Neon settings without touching the config. The value will stay there until your Neon gets reloaded, so you'll have to change the settings in the config if you want the changes to be permanent.

You need to use the /neon command to customize the settings.
All of these settings can be customized using the /neon command:
world, arena, prefix, color, color2, discordlink, streamlink or storelink
So if you want to change the value of some of those settings, you would do:
/neon <SETTING> <VALUE>
/neon arena myarenaregion

If you want to add a space to the value of some setting using the command, you need to run something like this:
/neon prefix this<space>is<space>a<space>prefix
The prefix will be turned into:
this is a prefix