Prototype needs 3 different voltages (3.3, 4.0 and 5)
Start with a 5V supply. Series resistor for the LCD backlight. 3.3V regulator (eg. AMS1117-3.3) for the 3.3V rail. Total cost less than a dime.
Reminds me of the old adage about asking a barber if you need a haircut.
Make sure to follow the recommendations on capacitors for the '1117, especially the output capacitor. The series resistor is the correct way to power an LCD backlight because the voltage is not well controlled, so a constant voltage supply can cause problems.