Don't forget Astral power. Balance somehow encompasses the entirety of celestial bodies for reasons unknown, and it was a deliberate shift compared to what we had before. Keep in mind that the Scythe also contains one of Goldrinn's fangs, though.
Still, until Blizzard makes a statement on the topic, the stance that they're like "real" suns holds more weight than that they're something else. It is notable that the sun and "regular" light(e.g. lasers) is generally associated with Nature or Fire spell schools, while the Light is always Holy, though, so Blizzard does appear to differentiate between the two.