1) I didn't said "comparing images", I said "compare displaying a string and displaying an image"
2) displaying images need to be done anyways, there is otherwise no point in showing only shortcuts. If you can't remember shortcuts, you sure would not remember for what those shortcuts were in the first place and you will end up scrolling thru the list and wasting a hell of a lot more time than how the quick-icon panel is integrated as it is.
Thus, 3) if you have 200 shortcuts wich contain the character "c" and you search for "c" it will be showing 200 shortcuts and images
(that is also how intelisense works: narrowing a list down as you type)...
Showing only 1 emoticon at a time by selecting it doesn't make much sense and I'm sure you will not be able to select your icon any faster... If it does, you already remembered the shortcut anyways (hence you have typed it and you knew what icon to select afterwards) and the whole purpose of the idea is lost (to not needing to remember shortcuts anymore).
4) The whole process of typing and selecting an icon will be waaaaay longer than it is now by simply opening a panel and selecting the icon you need.
/ 
