I've been in this situation for a while with my regular brokerage account and individual stocks are roughly 16% of my portfolio. I've taken it down from 30% this time last year and even higher a while back.
The lesson I've learned, when its time to sell, you need to sell. Don't sell them all in bulk and its fine to hang on to some for years, but if the reason you bought the company has fundamentally changed, then sell. I "lost" a ton of money hanging on to a dividend aristocrat after their long-term CEO and CFO retired and new management just wasn't cut out for the job. Missed 2-3 years worth of gains before I finally ate the taxes and sold the company.
There may also be some individual companies that you decide provide a lower return, high dividend, but have a low beta (less volatile than the market) which are worth holding and supporting a withdraw rate.
The thing I have to keep reminding myself, a huge chunk of the S&P 500's return has been Facebook, Amazon, Netflix, Apple, and Google. So the other 495 on average have "Trailed" the market. Its what makes individual stock investing so tantalizing, if you get one of these big winners, you win big. If you don't, you experience small, slow losses defined as earning a return less than the market.