I just wanted to add a word of caution here. I am not in your size category (I am 5"3!) but I think the principal holds true for most. When you begin running, often your aerobic fitness comes along quicker than your musculoskeletal strength. For that reason, it can be tempting to run more and more as you get fitter, but before your body is truly ready. This puts you at risk of injury. And given that you're a taller guy, you are putting a lot of weight and stress on each step, which means the risk of injury is even greater.
So I would think about adding one or two non/low impact cross training sessions to your week as you are building up your speed and mileage. I love the elliptical or bike, and I use a heart rate monitor to ensure that I'm getting my heart rate up high enough (otherwise I tend to slack off
Finally, I don't think walk breaks are a bad thing, particularly on long runs (like that impressive 11-miler you just did!). Jeff Galloway makes a great case for the run-walk method. I would just limit your time walking to maybe 20 seconds and then commit to running another mile or two before you walk again. Pretty soon you won't ever want to stop for a walk!
Good luck and keep us posted on your progress!