Higher pressure isn't better, nor is lower pressure. You want to be around 30-40 psi. Lower than 30 isn't good, nor is being over about 50 psi. 40-50 is okay, and usually results from the compressor being turned too slowly at idle.
You don't chage A/C based on pressure, you measure the weight of refrigerant being put in. An A/C system could have a rest pressure of 130 psi on a hot day, yet have only 1/4 pound of 134a in it. It could also have a rest presure of 40 psi on a cold winter day and be overcherged.
If you compressor is cycling very quick: 3-5 seconds, it'* low and needs to be recharged. It should stay on for at least 15 seconds or so before shutting off.