A few suggestions, since the author seems to be hanging around in this thread:

It would be good if plurals for variable names were the same as the singular, so that

light speed = 299,792,458 meters/second

Would be compatible with

time to earth=> 499.242173411seconds

Also, it would be nice if "per" was equivalent to /

Also, it would be nice if definitions didn't have to be

Single item on the left = many things on the right. For example, this would be nice:

Miles per gallon = 34 Gas tank = 13 gallons Range = miles per gas tank

So far I'm having a lot of fun and already posted it to Facebook.