Since the vocabulary for "human" is so limited why not use an earlier version of the word? The etymology dictionary tells me that one origin is Old French dating to the mid-15th century with a couple of variant spellings. I'd pick the most interesting: humaigne. It's an adjective form of the word and closer to "humane" than "human" but there's no reason why you couldn't use it anyway. It conveys "human" while getting around the perceived humdrum nature of the word and has the added bonus of a little lingual history.