By the way, it would be better if you post the new style you are looking for, in the "briefing area" so everyone can see it and everyone has the "rights" to design human/tree styles, because if you don't write it on the briefing then just the designer who uploaded first will be the only who will be able to use that art line.
This is how we manage here on LT, the first in submit an idea is the owner, but if the client post it for everyone then all designers are free to use the style.
Let me know if you have any questions.