Wow, you're probably the only person who has actually read the instruction manual. The information in it is so scarce, that I don't think anyone else has even bothered to look at it much.
Regarding DLC, there's been no other mention of it from I have seen. I really doubt there will be any, and even if there is, I doubt it would be anything that affects gameplay. Probably just alternate skins and such. But really, don't get your hopes up.