First of all, I'm aware that colored light is not currently possible in Minecraft. This is an idea for a red stone block that changes color based on the strength of the red stone signal it receives, and emits light like a red stone lantern.
Crafting ~ Three tinted glass in the first row, followed by two copper and a quartz block in the second row, and three dye in the third row- red, yellow, and blue. This recipe would make three Indicator Blocks.One side of the block has a copper-like pattern that resembles a red stone lantern, while the other is a solid color.
Use ~ The Indicator Block changes color based on the strength of the red stone signal it receives- by default, the indicator appears black. It becomes, (From one to fifteen signal strength), Purple, Magenta, Pink, Light Blue, Blue, Cyan, Lime Green, Green, Yellow, Orange, Brown, Red, grey, Light grey, and white. It also emits light when it is active. This could be used to create more complex displays and indicators using red stone, while also offering a new and useful application for the new materials added in 1.17.