You can use (If local codes permit) get a hydro pneumatic tank.
Some codes state that you must have a cut off switch in case the city water pressure drops below a certain pressure so you do not deplete the water from the main and thus causing a severe pressure problem in case of a fire emergency.( sucking the main dry)
Before you do decide to increase the pressure you 1st should get the actual size of your piping and type of material you have.
The velocity on copper tubing for example is around a maximum design flow of 6-8 FPS but on hot water this velocity should not exceed 4 0r 5 FPS as this would cause erosion problems.
Another factor to consider when arbitrarily increasing water pressure is hydrolic shock waves that can occur that can literally blow a piping system apart (Water hammer) besides causing more noise and other detrimental symptoms to your system, like piping chattering and hissing sounds.
You should take the time to figure your actual pressure requirements and and what is really needed to over come the friction losses of your system.