IMO, you need to look at your water usage in the bathroom sink! Do you let the water run while washing your face and hands, or while brushing your teeth? Do you let the water run for ANY reason? If so, IMO you should stop doing that!
The day may come when you are camped where you do not have ANY hookups, and no dump station, and, if you haven't learned to conserve water, you may run out of water or your holding tanks will get full (or both), and your trip will be over!
We have been known to go a week without filling either waste tank or running out of water. It is difficult, but it CAN be done!
Good luck.