Hermione and Lavender

I am a big fan of the Harry Potter series and the main problem I had with the HBP movie was the portral of Lavender Brown.
Now to be fair nowhere in the book series has there ever been a discription of what Lavender Brown looks like, Hell she was a Black girl in Prisioner of Azkaban but the the way she's protraied in the Half blood Prince book and Movie were 2 different characters
inthe Book she seemed more perky and outgoing with a lot of friends in the muggle world she would have been a Chearleader,I could see a deleated seen in my mind where Harry is traped at being her shoulder to cry on as the only girls in Gryphindor are Patil whos Lavenders BFF & Ginny whos Rons Litle sis.
in the Movie shes friendless, socially ocward and frumpy.
In my mind Laveder Brown should have been similer to Krum
where Hermione Looks at her a gets selfconcius about what she does not like about herself
someone who's tall,
has stait hair,
and perfetly even teeth
oh and only a dumb blonde would call there boyfriend Won Won