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Getting suggestions online for a backpack is just the first step. They all fit differently, and everyone has a different body. You want one that fits your body. Go to REI and try on every backpack they have. Make sure to put some weight in them (stores usually have sandbags for this purpose). Get measured as to whether you are a S, M, or L frame. This doesn't have as much to do with height as it does with your specific build.
Also, 75L is way too big for backpacking. The pack itself will weigh a lot, and somehow no matter how big the backpack is, it gets filled. Go with a 55L. My personal preference is a Gregory Z55. I've backpacked in the neighborhood of 3,000 miles and have a decent idea what I am talking about.