I have RSUs and in-the-money stock options granted by my company, both vested. I've held the RSUs for over a year, so I understand that when selling, I would pay long-term capital gains tax on the increase in price since the date of vesting. The stock options are unexercised, so I understand that if I were to exercise-and-sell, I would pay short-term capital gains tax on the gains over the strike price.
Is there a future tax benefit to selling RSUs in order to exercise-and-hold the stock options, which could later be sold under long-term instead of short-term tax rates? It seems to me that there's no additional tax benefit to holding the RSUs longer than a year, but there could be a tax benefit to exercising the options now and holding them, rather than just exercising and selling them at some point in the future. I'd sell the RSUs to get the cash to exercise the options, but that would be done mainly for diversification purposes, since holding onto the RSUs and the exercised options would concentrate too much in one stock.
Am I thinking about this correctly? Is there any additional consideration about what the current or strike prices are, or my future expectations for the stock? It seems that with exercising and holding, I would only pay long-term gains tax and wouldn't pay short-term gains tax on anything at all, but I wonder if I'm missing out somewhere else.