Just a bit of advise.
The get the biggest bang for the $$ you'll spend on your car to make it ''feel'' better, find a good/competent/reputable specialist and have your problems diagnosed.
Nothing is more frustrating (and expensive) than throwing parts at the car, not knowing exactly what is wrong with it.
Fuel pressure could possibly be a factor but there are probably 15 others reasons your car doe not ''feel'' to give you the performance you are anticipating.
JackD