Besides this being an amazing and brilliant idea for a mod, I have one issue. A toggle for the runes that appear onscreen (upon light activation) to be added for those that prefer a cleaner screen. Perhaps even being able to change what appears when your light activates.

You are in luck, I was finishing up the new release, one of the last few before beta. At some point I intended to add a toggle, but the forgot to. Thanks for reminding me! Anyway, to change what appears you can use a resource pack, just like you do with vanilla, only the the images you will have to edit are located in assets/lightwithin/textures/lights/runes/<the_rune>.png instead of assets/minecraft/texture/stuff