Just an additional comment - with the contrast control on the lcd, being a pot, you need to adjust this when testing the board and this can be a little labourious. On the other hand yu don't want fixed resistors unless you always use the same type and brand of lcd display. On one of my projects I had a spare DAC output (aduc834) and that solved the problem elegantly, another technique I've tried is a crude pwm and R/C circuit to provide a software adjustable contrast. The contrast is stored in eeprom (if you have it!) and can be adjusted via comms or user controls. All for less than the cost of the pot!

It's saved my bacon a few times.