Our daily use is similar to yours, and we find 65% is a good sweet spot.
We also try to charge only with solar and without using our Tesla PowerWalls so as to also extend their life. Our power company limits generation from our solar system to 10 Kw, although our solar array will generate a lot more on a full sun day (ostensibly to protect their transformers from too many people uploading simultaneously.)
If we use the car midday, I will monitor the energy generation rate and the energy consumption rate and adjust the charge rate accordingly. If it were a cloudy day, we drove morning and midday and didn't get home until 4pm (summer), I might reduce the charge rate to as low as 12v and then cut it as we stop producing, hoping the next day will be full or partial sun and then let 'er rip in the late morning, depending upon our projected driving needs for the next day. Not worried if we take off with only a 60% charge.
If I know we're going to need the full 65 (or more), we'll charge on a combo of array, PowerWalls and even allow some grid to go the full 48v from our Tesla charger. But this is rare.
Most common charge setting is somewhere between 24 and 32 volts. This balances well with other "house" draws, occasional clouds, and the 10kw utility imposed limit. If it's a full sun day, I'll often increase the M3's storage to 70%--we're trying to preserve the life of both the M3 and the PowerWalls.