I'm not quite sure what you're asking ...why would you want to change your name? I find hyphenated names a bit cumbersome. My wife has one, but that's only because she is from Norway and my ancestry is Irish, so she wants to maintain some identity. She often just uses mine when she's doing business to simplify things.
If you want to acknowledge your mother's family, it's up to you, but usually I associate hyphenated names with married women who want to retain their maiden name. The Spanish, I believe, often keep both family names ...perhaps someone more in the know can elaborate.
As far as changing your first and middle names, do what you want, but I think it's a bit strange. Your parents likely put some thought into what they named you and I think it slights them a bit by changing it. I could see if it was an absurd name, but yours really isn't.