I think we are looking for a certain profile of keeper mate, we want one that will hold their nerve in games with little to do, a keeper who will be commanding and authoritive in the box and also with his defenders breeding confidence and be competent under pressure when we are under the cosh. Especially with the philosphey of football we play i.e. playing from the back out.
You will always get keepers who play for the relegation threatened teams looking amazing, because they tend to be busier then those who are rarely called upon, id put Marshall, McGregor, Guzan, Heaton, Speroni and to a lesser extent Adrian and Fabianski in that bracket. We want someone who can keep their cool when not called upon often and can hold their nerve when they are under pressure. Be constructive in their decision making out from the back, while holding their psychological nerve through malaise and pressure. I think being the Everton keeper is a requires quite a wide psychological and practical skill set, depending on the game.