Well i think you could take some great advantage of the roof, you should make up some of the curtains that Phil has shown. That would look great having the roof with a sweeping rainbow effect
Use the floods for the walls and outline the gutter, roof lining and windows/doors and then use the curtains to cover the roof. the roof is a nice flat angled surface that could be used to great effect. Then i think you would have the house covered and will be able to achieve a lot of great colour transitions and effects.
So that would mean that you would have to get LSP 1.7 to make your life a lot easier