So there's two types of options, one of which have a tax benefit to exercising and holding shares for a year. I think the IRS now requires withholding the day you exercise to prevent large bills people can't pay if the price declines
Assuming they aren't the tax efficient type options, I'd sell and diversify once they vest unless you're already well past financial independence and want to gamble on single stock risk. (Most billionaires were millionaires who then took concentrated stock positions)
I get restricted stock from a large, slow growth company. Every year I get issued more than what vests, so I sell immediately and diversify. I already have plenty of restricted stock units and don't expect the company to out perform the index. If they do, I still win based on the four year vesting period.
Do you continue to be issued options? If you want to keep some or have a concentrated position, that's fine, just figure out what % of your net worth you're comfortable with and don't waiver on going above that amount. Personally I'd only do that after being financially independent with my "other" money.