Patching in a lawn with drought tolerant grass

My feeble attempts at getting some kind of lawn in our backyard seem to be continually thwarted each year. Upon moving in, our original backyard had a massive pit full of sand in it from the Previous Owner's sandbox. Since we started working on the house, the backyard has been a massive traffic area and a natural construction staging area full of all kinds of debris and materials for our second floor remodel and kitchen renovation, ruining any attempts we make at reviving it.

Add in the fact that our backyard is small to begin with, has several tall trees and buildings surrounding it, and receives probably only 5 hours of sunlight, it seems like a continually futile battle. So futile in fact, that Jen has repeatedly said she is ready to throw in the towel and just make our backyard grass-free and turn it into a big landscaped area with pea gravel or pavers etc.

Since we still haven't decided what we're going to do with this space (we need a plan!), I am making a last ditch effort this year to once again plant grass seed. Since I want to avoid watering the lawn, I found a hardy variety of grass called tall fescue that is promised to be drought tolerant once it's established and good for cool areas and even shady spaces. After some research, this showed up as one of the "greener" species of lawn grass that would be appropriate. I especially liked this description of tall fescue:

Low maintenance. Tall fescue has excellent tolerance for heat stress and drought. It will tolerate moderate traffic and infrequent mowing. This species is not well adapted to high altitudes.

So I've sowed some seed in one last desperate attempt to salvage a grassy spot in our yard. I figure we'll eventually carve out some kind of plan out of the grass anyway, but it would be nice to have a "green" canvas to begin with. It will be interesting to see how this blends in with the existing (spotty) lawn grass, which I believe is typical Kentucky bluegrass. I'll have to get some photos up of our yard soon to show its progress.