I use partial mash all the time. One thing I have learned, is to make the partial mash as large as you can in order to maintain steady temperatures.
If you just mash 2 lbs of grain, you will only be using about 2.5 quarts of liquid, which can be difficult to keep at a steady temperature.
I generally do 5 lbs of grain, use 6.5 quarts of water and have no problem maintaining temperature. I think the larger volume is easier to mash.
Recipe looks good. Something to think about to get a little more complexity, would be to split the Cascade and Cluster into 4 x 0.5 ozs additions at 15, 10, 5 and 0. You could even alternate Cascade-Cluster-Cascade-Cluster.