Well, this is a question only you can answer really. I would say read the entire manual to find out all the features on 2597. Then decide what are some/all features you would likely to use. Tweak the settings to your liking. Settings and features are "there" for you to use it really so there's a no magic button for maximum setting.
Yea, custom poi's are were its at, I'm really liking that we can just download and add them as we need them. Also, you guys seem to update them very frequently, which is very nice!