Taking 5v down to 3.3v with 10k and 5k Ohm resistors
Sorry, but that won't even work theoretically. You are ignoring the fact that the 8266 needs to draw current, and quite a bit of it. You can model your proposed circuit as 







simulate this circuit &ndash; Schematic created using CircuitLab

and the 8266 does not even have the decency to act as a simple resistor. From the data sheet you can see that the power supply drain can be in the range of 60 to 215 mA while operating, for an equivalent resistance of 15 to 55 ohms, and your standby equivalent is 3.7 Mohms. If you play around with your calculator you'll see that a simple voltage divider will not give you anything near the performance you want, and you'll need to step up to a voltage regulator. Start studying.