When using the feature slider with excerpt it is possible to adjust the height of the image. However, the picture is adjusted so the default ratio stays. This causes that the slider-hight is (when using posts and not pages) sometimes higher or smaller, which looks odd.
I would recommend using the zoom function of timthumb. In the shortcode I would give an exact hight and width of the image and the thumbnail is then zoomed in, in order to match the given size.
Is it possible to change that in the functions?