We could do a writing competition in July, with a set theme, if there's interest. Users could vote with thumbs (and yes, that could be abused, but for the writer, the appeal should be in doing some writing and getting comments).
Would there be interest in something like that?
While the interest exists, the thumbing, as you said could be abused. Some are thumbed down just for breathing.
As to the main appeal, there are risks in the comment factor as some people will blow a gasket if they are criticized and others will do similar if they see one of their unfavored people getting compliments.
I say go for it and see what happens, it may be a spectacular success or something with tepid response, only way to find out is by trying it.