The only people who use "shiny" to describe someone tend to be fans of the television series Firefly. ;)
Apart from that, not often. "Brilliant" is what we use for intelligent or smart individuals. Sunny can be used for a cheerful attitude, as in, "He/she has a sunny disposition." But I really think the word you're looking for here is "brilliant," which can, in certain contexts, be similar to "shiny."