Twint: It isn't too much stress for staff. Designing something isn't stressful in my opinion. When you get an idea, you draw it. When you draw it; you develop it until it's awesome. Then you make the graphic for it. I find that fun, if staff don't find it fun what's the point of working for a site like this without pay then?
Really, the creation of a new creatu completely relies on whether inspiration is found or not. So in the end, asking for a hummingbird creatu is not pressure or stressful. It's really providing ideas and leeding on to inspiration. Asking for creatu is not like a shop where you go 'I'd like this' and get it. It's really 'can we have this?' and 'it depends'.
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By the way, I wouldn't expect much if I were you guys. It's no longer the summer and most of the artists are students. So they won't have gajillions of free time to lend to res.