Hi Stacia,
I am new to etsy so I don't have a ton of experience, but here is a bit of what I think and what I have been told:
You're definitely right about your photos, they need more light and maybe a bit of context or surrounding decor, so as the buyer I can picture it in my own house.
I would change your product titles to reflect some of the same phrases in your tags. This will help your SEO.
Now this is just my opinion, but I would be less likely to buy a painting on canvas unframed. When I purchase a piece of art, I want it to feel complete. I think a framing your pieces (though I know how costly it is) can add a lot of value to your beautiful work.