My biggest suggestion is to work on nailing the focus. You seem to have slightly missed focus in both of these. It may just be that things "Look" sharp in your viewfinder and your diopter on your camera actually needs adjusting. My other suggestion would be to be more conscious of your subjects background. To me, a plain grey background is dull and boring and almost makes a subject look pasted in or at the very least, it makes the colors seem more flat or washed out. Some leafy greens or a rich blue sky in the background might help your subject 'pop' more.