As far as decisions, I wouldn't want the burden of making all the decisions so I'd like a girl who isn't on either extreme. So a balance but maybe leans slightly more submissive but definitely not subservient.
I'd like a girl who has opinions and can make her point calmly. I just don't want one of those girls who turns everything into an argument, yells to get her point across, or uses "because I said so" as an explanation for things. I want a girl who can offer her perspective and discuss things calmly while providing reasons. Like say "I prefer this because of x, y, and, y" and to do so without being condescending or demanding.
As far as sexually I'd prefer more submissive but I wouldn't mind her taking- some- control every now and then.