I certainly don't think there's a problem with devoting a small percentage of your portfolio (say 5%) to stock picks, or even a larger percentage split over multiple stocks, if you enjoy doing it. I occasionally do it with 5% too. But with retirement savings, I like to have as many guarantees as possible. By investing globally in index funds, I have as much confidence as possible that unless the world implodes, my savings will grow over the coming decades. If I pick individual stocks, even a decent number of them - holding say 10-15 at a time - and even if I actually AM really good at it, it is entirely feasible that I could lose money in the long term through bad luck alone. So even if I can increase my expected value through stock picking, I also significantly increase my risk.
I find personal finance fascinating too, but I prefer to spend my hobby time studying multifactor investing (regression analysis, etc.) and researching the optimal funds to achieve a moderate small and value tilt, while maintaining low costs and broad diversification.
-Your life or your money (personal finance more than investing) -The Warren Buffett Way -The Five Rules for Successful Stock Investing: Morningstar's Guide to Building Wealth and Winning in the Market...
My top book recommendation BTW would be the 4 Pillars of Investing by Bill Bernstein.
Of course most people wont suddenly have a 7+ figure portfolio, but will first have a 5+ and then 6+ figure portfolio. Yes I researched something for days when I was only investing $30K and that could be called a low hourly rate job, but I was learning an immense amount and now can do the same research in only a few hours all while dealing with a significantly larger amount so my "hourly rate" keeps going up.
And for what it is worth I am really enjoying the process.