Background Characters coming to the Foreground?

[kidzero7 at hotmail.com]

No: HPFGUIDX 27800

One of the things I love about the Harry Potter series is the 
abundance of minor and 'background' characters roaming the halls of 
Hogwarts. When I reread the series, I always find myself imagining 
the going-ons of these characters.

My question is this:

Has JK hinted at in her books or in the press that some of these 
background characters will come to the foreground?

I'm thinking that some of the "mudbloods" will play a bigger part if 
JK decides to really make the "blood issue" a focus of the series or 
one of her books.

Characters I'd personally like to learn more about are Dean Thomas, 
Lee Jordan, Cho Chang, Padma and Parvati Patil, and Justin Finch-
Fletchley.

Also, though it's not canon by any stretch... The Harry Potter 
Trading Card game requires that you choose a Character card before 
play. They have characters you'd expect to be able to play like 
Harry, Ron, Hermione, Snape, Flitwick, etc, but two minor characters 
that are playable are Dean Thomas and Hannah Abbott. It makes me 
wonder if JK had some input on what characters should be used and 
that possibly these 2 characters will play bigger roles by the end of 
the series.

What do you think?