TheGreekMythosGuru
Hecate is also a goddess of he moon, if you can keep her domain from being stolen or supplanted and take her as consort you could maybe claim the Sun domain when Helios dies(myths go all over the place so maybe you could create one in which the sun rests on the underworld during the nights?). The main problem with Hades is that anyone usurped his powers any time they wanted at least gods, did anyone important die? bring them back. did that mortal spite you? you can choose how he will be punished on the underworld. say nothing of the fact that is Hermes who drops people in the underworld and that son of Apollo who could just bring anyone back from the dead.