I'm getting ready to brew my 5th annual batch of my Good Morning Stout. It was inspired by Founder's Breakfast Stout. What Jon mentioned about the roasted malt is good advice for the porter. You can leave it all in and call it a stout lol. Either way, I think you'll beer will be great.
A pound of coffee? Yes, way too much. I don't use whole bean, but that's because I don't buy whole been coffee. I do order for Peet's coffee and they ground their coffee fresh before shipping mmmm. So I just use that. In a 5 gallon batch, I had 2-2.5 oz to the end of the boil. Then I add the that same amount to the secondary or keg. I bag it, so that I can easily pull it out when I reach my desired level of flavor. Obviously, with a lesser amount, you keep it in their longer. If you use more, you'll leave it in a less amount of time.
Sumatra is a nice roast for coffee beer.
I like WLP 001 with my American Style stouts/porters. I see that you are using all Maris Otter, so are you going with the English twist? I feel that the cleanliness of the 001 will allow the coffee to come through better.