Maybe a good direction to go would be to focus on being a servant for God. I am a Christian too. And that's why I asked if you were religious.

I think that focusing on your relationship with God may give you some peace. If your goal is to go to Heaven and you want to contribute more to society, why not start getting more involved at a church? Or get involved with the homeless? Or assisting the disabled? Or work at a charity? There are lots of ways you can contribute and all those things certainly seem to line up with your goal of going to heaven.

It's extremely rewarding too, to help people, even if it's not always easy or fun. I'm sure it'd fill the void for you of feeling like you're not contributing much.