[Imp]

As a side note apart from the graphics on the enhanced version making it a far better experience & saving you time the other enhancement's make keeping track of your units far easier & hence let you play faster & more efficiently.
The enhanced version therefore lets you play better & a lot quicker so you can play more battles in the free time you have. And that's without taking advantage of the extra features like the opfire filter.
If you play it regularly you are effectively cutting into your free time by not upgrading.