Thank you for your suggestions. I ended up using this plugin: https://github.com/c3mdigital/media-tools-for-WordPress
which worked great - it attached all my featured images perfectly.
I've been trying to figure out how to add padding to the custom widget that I registered on the home page but I think I am overlooking something obvious. I added this to my css but it doesn't seem to care:
padding: 0 0 30px;
Any help is appreciated.