I know full well that answers I give here will be blown out of the water in the event of actually getting into a relationship, but here's the rough ideal:

1: What traits are most important to you in a prospective partner?

Curiosity, playfulness, filthy-mindedness, independence and a passion for things they find interesting. Extra bonus points awarded for either mathematical inclinations or musical talent, as I've been unable to outrageously nerd out with, or duet with, any of my previous partners. Dance training would be nice.

2: What kind of role would you want your partner(s) to play in your life?

I would like to be someone's mutual hobby. There are a selection of important things in my life that I consider hobbies, and I would like at least one of them to be person-shaped.

3: How much time would you spend together, ideally?

I think this varies an awful lot over the lifecycle of a relationship, and is heavily dependent on the nature of the relationship and the habits and behaviour of the people in it.

4: How important is it to you that you share similar tastes?

Not terribly important, but I can't imagine myself being attracted to someone without a reasonable amount of overlap.

5: How important is it that you be ideologically similar?

See 4.

6: What, if anything, are your dealbreakers?

Irresponsibility and wilful selfishness. Abusiveness. Tantrums / terrorist negotiation tactics. Controlling behaviour. Gross insensitivity.

I think 6 is probably the most interesting question, since (seemingly in other people's answers, and definitely in mine) it appears to be a litany of horrendous past relationship experiences.