Personally, if you want to maximize output for space, I would go check out the Square Foot Gardening forum. As long as the water and nutrients are available, seems to me the major thing to worry about is cross polination...

Go for it!
Time will tell. The combination you have chosen seems reasonable as long as you keep up enough water and some basic nutrition, bearing in mind that blueberries are fussy about their soil, pH and adequate moisture. They don't mind a bit of shade from the hottest sun, but you had better prepare the right sort of bed for them.
Perhaps more important is to think about how you will prune and shape your trees in the space you have in order to manage pests, diseases and harvesting. Espalier is in fashion for good reason.

You've got a wonderful idea, make it happen and you'll see if if will become successful or not. Be sure that all of them are getting enough soil nutrients.