Suggestions

[Zenith]

I was under the impression that if we replaced Mandy's gym with a Dark one, she would take the E4 spot of whoever the Dark one was. But I agree, we should get IB's take on it.

I don't want to radically change the trinity. I just don't want them all to be immunities. With my idea, Light still beats Dark, and Psychic still beats Light. I just changed it so that Light only resists Dark (keeping Dark from being underpowered, and why wouldn't Dionare just use a Grass move on Dolphure in the first place?) and Psychic either resists Light or is immune to it (Kelvoyant beats Dionare with Fire attacks, while Dionare beats Kelvoyant with Dark attacks). Whether Psychic would end up resisting Light or being immune to it depends on how it affects Poison's use. The bigger thing to worry about here is the fact that Dionare isn't weak to Light, since Grass resists it.

Even so, typing alone doesn't make a 'mon bad or good. Just look at Infernape and Empoleon: massively different approaches (Ape's ginormous movepool and mixed attack power vs. Empoleon's 12 resistances and ability to switch in and set up), but both are (usually) sweepers, and both are OU.

Light>Bug? Maybe. It's really the heat that does the damage when you do that, not the light itself. I mean, they even catch on fire.