Well, the thing with the dead parents storyline is that it was once very overused.
Many story featuring orphans are pretty popular, because in those stories the author plays up the mystery behind the parent. Who was the parent, why did they do the things they did, why did they die, did they love the orphan?
And ofcourse the obligatory familymembers showing up.
Come to think of it, it you'd want to do a version of the above, you could also have a boyfriend/girlfriend passing away, or perhaps a brother or sister. And then have the main character discover that their beloved had many secrets.
Ofcourse, another subversion would be to have the main character know his parents very well, or be at an age where one's parents dying is not much of a suprise, or at the least, they can handle it.
Also, I like it, but that's because I'm a dork for mystery.