TankTeru for Maho, due to her similar role in the series, although Maho is shown to care significantly more for Miho than she lets on.
Tank Sumire for Erika. Both of them are the sidekicks to the main leader of the opposing team, and they both fall prey to attempts by their opponents to hinder them, leaving them unable to fight at full effectiveness.
Recursive Canon: Girls und Panzer draws a lot of influence from "Moeyo! Sensha Gakkou!" (and indeed, the book series' writer is part of the production staff, and the books are constantly referenced in-show). Guess what's included as a limited-edition extra for the fourth Blu-Ray release? A volume of "Moeyo! Sensha Gakkou"... except all about Girl und Panzer's setting.
The Red Stapler: The show put the real Japanese town of Oarai in Ibaraki prefecture on the anime map, seeing an increase in tourism especially after episode 4, which featured the town. For a more specific example, the hotel/restaurant that was shown wrecked by a drifting Matilda got a spike in reservations following the episode.
This  video gives a tour of Oarai, showing the real life version of locations that were used in certain scenes of the anime.
The annual Anglerfish Festival usually draws about 25,000 people to Oarai. On November 17-18, 2012, it drew 65,000 people, because of Girls Und Panzer
As noted elsewhere, Oarai has turned itself into an anime pilgrimage city, milking the show's popularity for every last Yen. Since the city was devastated by the 2011 tsunami, this has not created any fandom backlash. Comments usually go along the line of 'they really need it'.
Yuka is the driver of the M3Lee tank, Karina, while Sonata (Juliet Simmons) plays Aya Oono, one of the gunners for Rabbit Team.
Makoto (Molly Searcy), the most cowardly of understudies for the next generation of AKB0048, plays the tired, sleepy, but smart driver of Anglerfish Team, Mako.
Yuki "Yukirin" Kashiwagi the 6th (Margaret McDonald) plays the show's protagonist and leader of Anglerfish Team, Miho Nishizumi. (note: Margaret is credited as "Meg".)
Two next generation AKB0048 understudies, Kanata Shinonome (Genevieve Simmons) and Mimori Kishida (Carli Mosier), play Duck Team (The members made up of the Volleyball Club) members Noriko Isobe and Akebi Sasaki. Also, AKB0048 Successor Minami Takahashi the 5th is the driver Shinobu Kawanishi.
Tomomi "Tomochin" Itano the 11th (Allison Sumrall) commands Rabbit Team as Azusa Sawa.
Tsubasa Katagiri plays Tankery instructor Ami Chouno. She also doubles as Mallard Team's driver, Moyoko Gotou.
Megumi Wanaguchi (Meaghan Avocado) is Yuzu Koyama, the Student Council's Vice President and driver of Turtle Team (which consisted of the Student Council members).
Chieri Sono leads Saunders College High's Tankery team as Kay, while Orine Aida is Saunders' cheating third in command, Arisa.
Excel♥Saga: Excel is Saori Takebe, the radio operator for Anglerfish Team, while Hyatt is Karina, the driver for Rabbit Team (they also would go on to be in MariaÜHolic, about one year later as Kanako and Mariya).