What OBD II data should I look at?

So I have this project going where I have a Raspberry Pi reading OBD data and the plan is to have it display on a small screen. Basically a DIY scangauge or ultragauge.

I am trying to decide what to display on my screen that would be useful.

So far I am planning on:

MPG (calculated)
Air temp (ambient and intake)
Battery V

What else can I display would be useful to monitoring the health of my truck? Any suggestions?

If anyone is curious here is a list if things I might me able to display: http://python-obd.readthedocs.io/en/latest/Command Tables/

 

Oil pressure, water temp

 

I like “distance to empty” on my Scan Gauge. I think it’s calculated based on that tank’s average MPG.

 

Transmission temp.

 

Thanks for the suggestions!

 

I just got a scangauge for mine and I’m using the mpg,water temp, volts and rpm