while still being basically evil and controlling in a very sane and socially acceptable way. He wasn't faking it, he was never "good", but he was in control and competent.

Sounds interesting. I hate how comics conflate mental illness with 'evil,' and sanity with being 'good.'

I've met quite a few people who are, not to mince my words, fucking nuts (at some points of their life; most people with severe mental illness have episodes of relative health).

Many of those people were also fundamentally good, kind, likeable individuals, and that shone through even in moments of florid psychosis.