Ok, have decided to try again and "embrace that role", but in a different way.
I've got in contact with someone I used to work with, first meet today.
We'll see how it goes, I guess.

team-playing doesn't seen to be a natural trait for writers

I think any writer by their nature (regardless of genre) has a certain degree of arrogance, thinking their idea is the best in the world, etc. So sometimes when two writers get together, the egos clash. But it's the same with any profession really, but writing seems to be the most intense that I've seen.

If I had the choice, I'd love the chance to co-write with someone. But I's probably want to work with a female writer than a male one--simply to get a female's perspective on the novel (as they count for most of the readers out there). One critism I've had for some stories I've written in the past is that my females tend to be a little "oversexed" so I'd love it for someone to tone that part down.

With regards to what you said about the simpsons, it's usually the general way for any show in America where they have a writing team, who all put their own ideas in bit by bit. It's just lucky that the Simpsons have such an amazing writing team that all seem to gel together.

Good luck with it anyway.

it's just lucky

But is it?
I reckon there is a lot of very deliberate management to achieve that luck! It helps to have the budget to afford the right people, but you still have to be able to recognize right from wrong and I doubt they leave it all to chance.
Now I'm back into it, I'm certain that we are not setting up the way of working to get the best...