If your stock doesn’t move much and is relatively safe, then I’d wait for the LT gains, but remember that the state (Ca.) still taxes you fully on it (I could be wrong about this, but unfortunately, probably not).
If you have options, you can exercise and sell those before selling the ESPP because you’ll get whacked on the ST gains anyway, that’s what I always try to do.
Of course my company had stock that was all over the place, so my perspective is different. I saw a lot of co-workers trying to save a some money on taxes get hit with AMT (buying options) or seeing the stock drop 50% before they sold their ESPPs or options.
So from my perspective with the volatile stock, if it’s a good time to sell, don’t think about the tax consequences.