1) Do you think that anyone gets "lost" in the Weasley family? It's a big group with a lot of strong personalities there. Does everyone get a fair look in?
I think everyone get a fair look in...but to a degree i believe that Ron is less attened to when it comes to his parents. They dont neglect him or anything...but the face that he has 5 brother above him and a sister below...he's often not as seen.
2) How do you think that Molly and Arthur's relationship has impacted on their brood and how they see the world?
Yes. Parents have huge imapcts on their children's ideas and views of life. Though i am guessing Molly and Arthur have old their children that they dont have to beelive what their parents are saying.
3) What do you think about the fact that we rarely see the entire Weasley Clan together? Is this just "bad fortune" or is there something askew with the family dynamic?
I think that it's just a case of bad fortune. The fact that Bill and Charlie and now Percy have each finished school and have gone out into the world means that tyey cant exactly get home just beacuse everyone else is there. I think that the Weasley family is just a normal family with grown up children doing their own thing.
4) How big an impact did Percy's abandonment of his family from GOF to DH have on his siblings? We've seen that Arthur gets quietly angry and Molly gets tearful. Is there anything Percy's fellow siblings could have done?
I think that it did disrupt the whole balance of the family. Molly for one has always kinda relied on the fact that her children are safe and around her. And Percy storming off like that has knocked her around a bit. It made her defeces lower and made her more stressed. She would have been wondering all through that time how he was and whether he needed her help or something. Arthur would have been the same...but was more able to keep it toghether...and just blew his top occasionally. He would have realised that Percy could take care of himself, no matter how angry he was at him. Molly - being his mother, would stress about him constantly.
5) The Weasleys were like a real family to Harry. What's your view on this given that there were already 7 kids in the family already?
I think The weasley's subconsiously "adopted" Harry into the family. After leaving for Hogwarts...Harry came across the Weasley's, and from then on almost had a mum and dad to love and to love him. Molly actually trats him like a son.
7) Who are least alike in the Weasley family? Who's most alike? Is there an element of peer pressure on those who are least like the others? Who's the most misunderstood?
I am least like Percy. I am not stuck up and i o NOT do good at school lol. I am most like Ginny i think as she is not only a girl, but she has the same personality and attitude that i have. The most missunderstood would be Fred and George. Molly always thought they were going to waste their life with the joke shop, and really it was an awesome buisness for those two. 
Given Arthur doesn't seem so highly motivated, do you think that his children are "over achievers". The have been very successful in their fields and indeed in school (think quidditch captains, head boys, prefects etc). If so, where do they get this drive?
I think he is motivated,. Just not how Molly finds it best for the family and though he isnt a high acheiver...i think he has achevied what he wants to acheive, and that he is happy with his life. Forget Question Six...there was a poll with it and i forgot to take that question out.