Both Aquila matte and merino will do fine if you love slouchy look. Nappa has a bit of structure compare to these two. I personally prefer Aquila matte so I may be bias. Aquila matte has a bit of velvety feel to it and it feels heavenly to me. But if counter any oil or scratches, Aquila matte may show coz it can absorb those things. You can rub the scruff off, but it's the leather that will show the life it's been through in the most beautiful way.
If you want your bag to always be pristine, pick merino. But if you want some wear on it, pick Aquila matte. But if you prefer it to hold it's shape along the seam area with sheen, pick Nappa.