I am testing aREST to drive the ESP.
I am only flashing an LED at present but it seems to be a good foundation to build a complex custom control page with basic html that you can understand (there are too many complex control pages out there for me!).
Early notes and aREST links here -
http://www.sunspot.co.uk/Projects/raspberrypi_LAN_master/raspi.html
Please tell me if you add i2c devices - that's my next objective