I'm tech-heavy in my individual stock holdings, but my mutual funds are very diversified. I follow one biotech that I will most likely take a large stake in.
Most of my retirement accounts are in mutual funds and some of my non retirement accounts are in funds. I have index funds, REIT funds, International Funds, small cap, value, etc. I like the fact that by having a well allocated portfolio of funds, I don't have to track it daily. They all have their seasons.
I also own a house in a hot market in So. California, so a large chunk of my net worth is equity in that. My best advice to any young person is to buy a house as soon as you can. Forget fancy cars and other non-necessities. I bought my first house at 24 years old on my own. I'm now on my third. Real estate has been by far my most profitable investment.