That sounds gorgeous, but I know what you mean about it looking like a store. I’d try filling in the bottom shelves (bottom 3 if there are 6 shelves) with books first, and then doing decor on the top sections. That will give it some grounding and make it less like items are just floating on all the shelves. You can mix more books into the upper sections as well, mixing some laying down and some “normal”. As far as how many items on each shelf, I’d try to mix that up so they aren’t all the same. Some may look great with one larger vase in the center and others will need more of a mix.