I'm doing the exact same thing; warrior/shaman.

For the quests, Jamba does do what you're talking about but I'm at work right now so I can't look to see which settings it is. There are only a few options in the quest category so just make changes and test it out.

Keyclone and the like, broadcast keys you press from your main to your slave windows. So for healing, start by making a macro on your shaman to target your warrior and cast a heal on him. Put it on a hotbar on your shaman and press the corresponding key on your warrior. That's a quick and easy way to get started.

Keyclone is easy to use and works very well. It may be a good starting place to get you playing/having fun.

Isboxer has many more features but it's harder to learn. It's definitely worth the time though. I took a night and switched over to it and I couldn't be happier.