That's the absolute joy of fanfic. Yes, it can be depressing. I mean, does he even make it to the modern era or does a disease wipe him out, or the nuclear bombs, etc...
However, as writers, we can make his story anything we want. Knowing the man the way the show has portrayed him, chances are good he's going to work to excel at everything he does, OR he will just give up and move on into obscurity - it could go either way. YOU get to decide as the writer (I like my taiyoukai powerful and rich, but then that's how I like my men too
) and that helps remove the depression.