These are very nice and, while simple, display a great amount of technical skill gained over years of drawing. I believe your commission prices are fair! It's always good to test the waters with a bit of field work, too, see what kinds of commission offers sell (ie, if uncoloured lineart/sketches sell better than colour illustrations, you could offer small discounts to repeat clients for them).
You mention you're not as established but no worries, this is a personal, customised service you're offering and doesn't necessarily need to be leveraged heavily into pricing early on. From these two pieces, I feel you have a very whimsical, storybook-like style that would appeal to audiences looking for caricatures of friends/family.
Have you considered your target audience? With the holidays so close, if you're concerned about prices being too-high, you could up the ante with simple templates to construct cute, festive themes.