I wouldn't worry about things that can't be help. You guys have school to do and that's most important. Just do what you can when you can and it will all fall in place.
We have accomplished so much ready, and I'm sure all the essential icons have been made. Now it's all about digging further into the Portal and getting at the heart of things, watching movies and playing games that haven't been seen in months or even years. Now we really are getting to the real dirty work of things and it's all about progressing forward. As long as you can devote some time to make a few icons here and there, it will help us to reach our final goal; every little bit really does help.
And don't worry about what you could have done if you have more free time, but rather what you can do with the time you do have.