u/Head-Ad-8160

I have an off grid cabin where the water feeds down from a cistern on the roof, through the 12V diaphragm pump shown above. It provides nice pressure for washing dishes in the kitchen and from the faucet in the bathroom, however, the water pressure in the shower is incredibly weak.

To improve this, should I (a) replace the above with a stronger pump (if so, spec recommendations welcome), (b) install a second one of these pumps right by the shower, or (c) run a dedicated line out of the water heater to the shower with its own pump (and if so, would the above be sufficient or should I be trying to get more powerful)?