Actually, I changed my surname to something else for a specific reason - it is a name found in English, American, Russian, Eastern European, French, Spanish, South American and has a Middle Eastern derivative root.
The reason I chose it is because it's impossible to "pin down" to just one particular culture or place. I don't like the idea of being judged for my surname, but I also want one that would fit in quite easily in my own country (it does) and many others without looking too outlandish. So I managed to find this one name that is spread out all over many countries, and it also happens to be used in astronomy, which is an interest of mine. (There are stars named for it).
So, by all means you can change your name to something if you want it to blend in more, or if like me you want it to blend in, while being at the same time elusive to racial or cultural origin, as well as a bit unusual and related to something you like.
About having to spell out names for people - previously I had a fairly normal name and people still didn't get it. The teachers at my school got the gender of it wrong (maybe it was rarer back then), and my original surname is simple but I ALWAYS have to spell it out for people because they assume I'm saying something else or they can't make head or tail of my accent so they assume it's something else. (I've had people say I sound American which is bizarre, but they seem to think I'm saying some similar-sounding word to what it actually is). So having had people fall over my very straightforward name all my life and having to spell it out for them every time anyway, I figure, who cares about spelling out the new one for people.