Would be much easier if you show more puctures from different angles.

Treasure, you have created a really tough situation here. Between the 2' depth, the overhang from the eaves, and the western sun, this bed will be difficult to keep enough moisture in to grow much in. I am also concerned about the house; since you built the bed almost up to the bottom of the clapboards, you have created a potential problem with any moisture in the bed being so close to the house if you decide to irrigate.

Would you be willing to reconsider a redesign of the bed before thinking about plants in order to prevent structure problems with the hosue and plant survival problems?

Here's a few suggestions. This bed is very tight. You'll need to keep the shrub chopped off at the back side in order to keep it off of the siding. Next time you make a bed, make it deeper (front to back.)

I hear you on the iris. And if they get grass growing in them, you're doomed. I like yardvaark's suggestions otherwise.

I agree that this bed is quite tiny and therefore will suffer from heat and lack of natural water (because whatever is planted there will be very very close to the house). Perhaps you could look at a low groundcover that would survive these conditions - ajuga maybe?

I feel like the left side of the backyard looks much heavier and you need to plant something under the windows from the right to balance the picture.

"...but they only bloom 2 or three weeks and after that, how attractive would they be?" I guess that depends on if you like, clean, thick, vertical, bluish-green, long-lasting grass-like foliage. While I'm giving you a specific example, it doesn't mean that you can't pick something else. There must be bucketloads of perennial choices.

Siberian iris look quite nice even when not in bloom - much more so than bearded iris. I do like the idea of extending the bed though as shown by vstavay. That gives you a lot more options.