If Emma Watson doesn’t screw up her fame, she’ll likely evolve to be Hollywood’s Hottest Property. Aside from the fact that she’s current, she’s also a pretty tolerable actress. She isn’t like most Hollywood tweens that was tagged corny and idiotic because she managed to pull herself out of that spot. Radcliffe’s extra-Potter activity is Broadway and I can’t see giggling schoolgirls getting chirpy on those kinds of entertainment. Watson is frequently seen in galas where people check out her fashion...
Although if you think about it... Justin Bieber kind of owned Radcliffe believe it or not.
I guess amongst the kids, these two have the biggest gain to continue acting in Hollywood. Radcliffe may find himself playing non-titular roles to at least shield his Harry Potter-ness. Watson on the other hand will likely score Julia Roberts-esque roles. I don't know if she's ready to bare but she needs to have an extremely superb movie to do such because that move will definitely bring fanfare. Amongst the other kids, the fact that the Potter fame may or may not tag them could work for them. The Ron kid may score offbeat roles and while the Draco kid will have an upcoming movie, the verdict is still out with regards to him.
Hopefully most of the kids would find work outside the realm of magic.