That diagram (post#5) halves the 3.3volt drive voltage for the fet.
1.65volt is not enough for most logic level mosfets to fully turn on.
Change the pin<>gate resistor to 1k, and the resistor to ground to 100k.
Or use a small-signal NPN transistor there, with just a 10k base resistor.
The p-channel fet with 10k gate pull up is ok, as long as it's one with very low Vgs(th).
Leo..