Honestly my view is that whether Zodiark is good or evil is, in the end, almost entirely irrelevant. The bit that matters is that his (self-proclaimed) representatives, the Ascians, are definitely evil.

By which I mean how every Ascian we've met has been pointlessly cruel, including to their own. The first time we see any Ascian care about another is in the Eden raids, with Mitron and Loghrif, and at that point it was already twisted into a creepy possessive thing. Even Elidibus was concerned more with his (imperfect) memories of the Convocation, not what the Ascians had actually become.

And when the Unsundered all perished and the Sundered were free to do their own thing, one of them went creepy-possessive, and another went "let's destroy the world".

So if Zodiark wants to be seen as not-evil, he'd need to fire all the Ascians and get better employees.