What is the best design pattern for a GIS application?

I was about to start writing a standalone Geographical Information System (GIS) application in Python to use shapefiles to draw maps with some simple controls for zooming and scrolling, similar to what one might see in Google Maps. Using an object-oriented pattern to separate geographical (model/abstraction) data from the GUI presentation seems to be a good way to go. I see several candidates: model-view-controller, presentation-abstraction-control, and model-view-presenter. I suspect that any of these could be used, but that there are advantages and disadvantages to each. Does anyone have a recommendation on the best of these three design patterns to use? Does the recommended pattern change if this were to be developed as a web application instead of a standalone application?