The GUI looks messy. The tabs have both a text and image which needs to be either or not both

I have formal training in GUI design and can tell you this is not a good idea.

The reason interfaces have the ability to show both text and image is called "incremental familiarity". When first using an interface that has images, some people may not remember (or even know) what a given image means in *this* particular program. Hence the text beside the image. Over time, when they get more familiar with the interface, they can go into the options/settings and select to only show the image.

Other people have issues with cluttered or "busy" interfaces and tend to shy away from lots images in an interface. These are the people that would go to the settings and turn off images.

Often, an icon means two different things in two different interfaces. This is usually because the developer was too lazy to find the "perfect" icon and re-used an existing one for a different task. An incremental Familiarity interface helps to mitigate the confusion caused by these lazy bums.