Ornamental Grasses

I am a shade gardener above all else. I know a lot about shade gardening. I know some about sun gardening. I know almost nothing about ornamental grasses.

We have one sunny spot in the landlady's garden which is wanting a few grasses. Landlady likes grasses. There is sun. Yay! It's behind a nine-bark which is about 3' tall now and will get a couple feet taller. I have a very small space - a sort-off 3'x3'x3' triangle behind the nine-bark. The grass would serve as a back drop for the shrub which is a bronzy-russet.

My questions are:
1. what's a good grass which won't grow wildly?
2. what's good grass that has seed heads that get over 5 feet tall?
3. what's a good grass that grows fairly erectly (not so 'weeping')?
4. what's a good grass that has some rusty-red tones in the stem or seed head?
5. what else should I consider?
6. what grass fits all the above descriptions?

We're in zone 6. There is winter protection and the sunlight at that spot is not quite full-sun.