If I built something like this, I would want to do everything under the cover. This would include putting the things down when I empty one of the compartments, being able to open all the compartments fully, having the ladder feet sitting underneath the cover, etc.
It sounds like you're trying to balance overall aesthetic with practicality. While I agree this is important, any kind of structure is going to adversely impact your lot's aesthetic. Those that are detractors will always say how bad it looks, while those who are owners like you - wow this is a great idea. I would aim for the latter, and it seems you are too because you are thinking about which way the wind blows, how to back onto the driveway, and so forth.
What you didn't mention here is future upgrades. It might be helpful to have electric for waxing or a ceiling fan or have a couple sides partly closed to store things, etc. What about a drain- could you tie into the house sewer and get a easy place to dunno for incremental more cost? Everything would be below the slab anyway.