I'm not an expert photographer. Far from it. But, here's something I have learned: PicMonkey (and similar programs) is your friend. Here's a set of three photos, untouched:
Using PicMonkey (this is not sponsored btw, I just like them) I made a collage with a light blue background to match the sky:
That added more visual interest, but doesn't solve the exposure problem.
Now, I took the collage and (in this order) went into Exposure and increased the brightness to 20, increased the highlights to 40, increased the shadows to 25, and increased the contrast to 10. Then I went into Colors and increased the temperature and saturation by 5 each. This wiped out the sky, but helped Max (the focal point) look better.
Point being - play around a bit. Change the order and percentages of what you change. If you have more advanced features and can do even more, awesome. And, always save the originals!