Since I'm not really planning to look for a job, my main worry was potential visa issues. But I haven't had any troubles visiting the few countries I do need a visa for.
How are you in a position where looking for a job in the future is not really necessary?
Bitcoin.
That's an awful lot of faith in virtual currency and its speculative nature to be betting the next 50-60 years of your life.
I can't even tell you how many pen testers I know with criminal records. Somewhere, someone will hire him to do security.
Who is to say xe didn't buy a bunch of it at $1 and sell it off, making millions, when it hit $200-$300?
Diversification is pretty important if you want to keep any kind of currency for 50-60 years.
Talented hackers are not exactly unemployable.
The other side to that is that if you appeal, and lose, you can come off worse. So even though a criminal record is "something", depending where the lawyers feel your chances are, it may be best going along with it.
I suppose it depends on what that means for a minor in Finland.