User blog comment:Dustpirate/Do Stores become unnecessary?/@comment-5039776-20120618144108/@comment-5039776-20120619113021

Get 24 street lamps (8 each, the maximum), some firefly lamp 1s (8 is max) and then for highest return per pixel, go for Venus fly traps. Simply consider the return per pixel per day.

My spreadsheet (see link in my home page) tells you,the return per pixel per day for pretty much everything (decorations tab).