As I already wrote, I do tell some people that I am a hacker. Most of the times this a result of the question: 'So you are a hacker?' After I explained what I do.
Saying you are only a hacker if your peers call you that just raises the mystery around the term hacker.
Last part of your statement I fully agree to. Hacking at first has nothing to do with software or hardware. For me it is using stuff in a way that is was not intent to be used. Being in Africa right now, I see a lot of clever hacks, where people use for example climate control devices to get more or less clean water, reusing garbage to build new stuff and so on.
I am more concerned about the phrase 'expert'. This is imo something you can not label yourself. And even if.. it sounds always kind of strange to me.