Gabriel,
JFBConnect will make many of those steps easier. We have an easy way to add Like buttons and Comment boxes to other content. We also have a way that isn't very publicized that you can add a Share button to content with a description of a page (or a score or whatever you want) and then the user can add their own message before it's posted to their wall.
Alternatively, if you wanted to post scores automatically for a user to their wall, JFBConnect has a simple function you can call in PHP with the wall post details.
As for comparing results against Facebook friends, that may take more work. Honestly, you'd likely start off by leaving Facebook out of the equation. Have some method on your site of comparing a user's results with every other user. Then, with JFBConnect, we could help you look up that user's friends, match them to any user's on your site that are also on Facebook and the user's friends, and then just compare that subset. I don't *think* it would be that difficult if you already have the on-site comparison ability, but I don't know that extension, so I can't guarantee it.
Finally, we don't offer paid development. If you don't know PHP code, you'd need someone who could implement the features above. With a subscription though, we can gladly guide that developer through the process regarding the Facebook side of things.
Hope that all helps and explains, but if you have any other questions, just let us know!
Thanks,
Alex