Very similar to Redstone Relay but working in reverse - outputs redstone signal based on current FE and maximum possible FE flow in wire as floor(15*FE/maxFEflow).

"Redstone Inducer" is probably a better name.

Also, using this device people can power their existing Redstone lights. A "Redstone Inducer" is probably simpler to implement than a bunch of lamps.

Maybe, not a priority.