ESP8266 Community Forum

Nice job!
Take a look a this ST7032i I2C Display implementation http://www.esp8266-projects.com/2015/03/display-time-st7032i-i2c-lcd-display.html the LCD_Write and LCD_Print_Values functions might help you with printing numbers.

Here is an UART TFT LCD, it supports WYSIWYG editor to build your GUI in PC and download it via USB.
I think it is easier and very cool to do your project.

It can be controlled by Arduino via UART, so just use the Serial.print() you can make it display many images. And you can even build Font by yourself and download to the LCD.

tutorial and video:http://blog.iteadstudio.com/product-preview-nextion-in-an-arduino-project-3/