Well I really think that the new 4 characters look quite..bland.
Lets compare!
This is the orginal 4:
The great thing about them 4 is theay are so stereotypical it hurts, and not to mention "colourfull".
Now the new 4:
They really don't look that stereotypical(apart from the guy right next to girl) and less "colourfull".
In a fight for looks the original 4 would win cause they stand out of the crowd more. Cause...well...it looks like the worst team line up for a zombie apocalypse. The Army Old guy, the High school Girl, the Clerk and the Biker.
The new 4 don't really stand out apart from many one guy...You have some kind of a thug taken from the worst Travolta movie and that really looks like Edward Norton now that I think of, a black girl which seems to have 16 years from that picture,but!, aparently is some kind of news reporter(Which you can't tell from that picture.), a school teacher(he is called Coach the only character name I know) and the Scout from TF2 who is a mechanic(which you cannot tell from that picture.). Edward Norton and the Scout have almost the same colour scheme in their shirts, the coach shirt is beyond awfull, and the girl...actually the only good designed character but its missing the stereotype. Valve says she is a reporter but it doesn't give that feeling.
The original 4 you look at them and you imidiatly recognize and know what stereotype they are.
To improve the new cast, the Scout and the Coach could use some revamping, some changes to the lady and keep Edward Norton.