Hey,
I'll give you more details later when I go back to the office and meet my colleague, but I would say is to work on the font itself, to make it more intriguing, try to explore the third dimension or to make the word explode of joy. :)
coming to submissions: #8 is funny, but we are not so keen on characters, while #7 is quite "straight forward" why not try something really different on the "Z" to make it more lively?
I'll try to post some reference when I'm in the office in the morning.