And/or be “the bad guy” who implements rules and limits

Be the bad guy. As a parent, you're not your kids beast friend. You shouldn't be. You should be setting examples and teaching them to be good, upstanding, reasonable adults. This involves telling them no and setting boundaries. Fair, firm and consistent.

Agreed - though I would add rationally empathic.

I've found that if I follow-up, immediately, with an understanding of my child's perspective, they are more on-board with what I am modeling. Then, it's not just about me being the authority, but me demonstrating why I have 'a better idea'.

It makes it almost effortless to be fair, firm, and consistent, and was the one thing missing from my own rather draconian childhood.

Trying to be good at all times is a tremendous trap. They don't say that good intentions pave the road to hell for no reason.