I personally wouldn't do it. I think it's still funny, and if everyone around here still knows you under this username, it could get confusing. But if you aren't happy with it, go ahead. It's really up to you, not us.
I agree with 2kimi2furious. Changing your username is entirely up to you. Personally I’ve changed mine around five times and sometimes I have to explain to old friends from here that I’m the same person as the other usernames I had. I wouldn’t do it, but again, it’s your choice.
I think you have a fine username but in my experience if you think you want to change it you should just change it, or else you will just keep going back and forth! I don't regret changing my name even though my old one was very well known.
I like your name a lot. In my memory it's associated with your previous avatar however. Though, I'm somewhat curious what name you'll go by if you're gonna change it.
It's a funny username, it will grow on you besides it's not like a 13 year old's xbox username like: XxX_Death_Destroyer666_XxX. Usernames shouldn't take much thought. My username is named after my dog for example.