This is a very worthwhile effort. I get a very readable graph if I turn my Nexus 7 horizontally, set 'low altitude display' and zoom in 2X. That makes the fonts big enough to read easily and displays the altitude of interest (up to about 10K for me). And it allows me to see the wind speed graph at the same time.

The 'time warp' slider is informative and helps to get a feel for how conditions change through the day.

Here are some not necessarily good ideas off the top of my head:

It might be useful to have the option to set surface temperature automatically based on forecast.

For eastern pilots,it might be useful to have the option to display the data to top of 10K, but only if you also had the option to choose a larger font.