First of all, thank you for the purchase!
Regarding the image slider: the image width and height had to be hard-coded in order to make the theme responsive (i.e. rearrange automatically depending on the screen resolution and type of device). This is why the image is being resized according to the pre-set dimensions (950×330 px). I would recommend cropping the slider images to these dimensions in order for them to appear “as-is” in the slider (in case you do not have an image editor installed, I can crop them for you). If you wish though, I can try to modify the template files so as to increase the image height to your preferred figure. Let me know what you think!