I completely agree with every bullet point you made, so I'm not much help. I look at your picture of the garage and don't see a problem with it at all. If the pile started overtaking the garage, then the bedrooms, then the hallway, you'd have a problem. I think you should just try your best to find a storage home for the boxes, keep them organized and neat, and call it good until you find the "perfect place" for them that you're seeking. I find that over time I'm able to filter through the boxes and get rid of things that I realize are no longer needful. I'm sure you'll find a balance.