My first impression is that the rise on the stairs is a little high for a person scaled that size. In RL, they look like theyd be about 10 inches high (Im guessing youre using a 6' high man as your "ruler"), while the industry standard for safety purposes is more like 7 or 8, depending on where you live. Curiously enough, if you increased his size so the top of his head was more or less level with the top of the mezzanine and then scaled up the height of the bannisters on the mezz level, the scale of the entire place would probably snap together just fine. And Im really not sure about the railings. Just for myself, Id lean more towards the glass wall idea: it would give your space a cleaner, more "Euro" feel in the design, particularly with the nice curves in the upper-level balconies. But with the bannisters and railings on the mezz level, again, Id watch the scale: right now, they look about 4" thick, and thats huge for a railing. But feel free to disregard; this is all just the wanna-be architect in me talking.