The pinstripe pants would add accuracy, but I don't know that they look better. That's up to you.
The only thing I'd say makes it look more costume than reality is that it's incredibly clean.
I'd say, some roughed up hairsprayed hair and maybe rough up your garments a bit (just some dirt or run sandpaper over some parts) would really help this to look authentic.
Cosplays in Progress:
Haruno Sakura (Shippuden)
Theodora (Oz the Great and Powerful)
C. Viper (Street Fighter)
Twilight Princess/BRAWL Zelda (Green BRAWL ver)
Tharja (Fire Emblem Awakening)