The amount of effort really goes down once you keep driving like you are for a while. About one month into starting to use P&G constatly I was thinking, "is this worth it? Its a ton of work." I kept at it, and now its just normal driving. I don't think too much about it and it seems really weird if I don't engine off going down a hill. So, it does get easier.
With a little more practice you'll see much better mileage. For instance, just look at my mileage for the Paseo (click sig). It has slowly increased for a long time now, and I really haven't ecomodded it at all yet.