From 2ch:
About the pantsu:
He was in doubt about how much to show. After talking to both man and women, the woman said "I think you'd better show them". He tried on that PV and became convinced.

Ikuhara's family was watching the talk show.

About the comic: The story from the show would be difficult to translate into manga, so they will be completely different, but they will use each other's work as a source of inspiration.

Q.What is Yuri Kuma Arashi?
Yuri = "the type that's hard to explain to your family"
It's a story about yuri meating scary bears.
"Like a sushi man meeting a space fisherman meeting a mole person, it's an unbelievable combination"
The bears are cute in the PV but scary in the show.

Q. But why bears?
Because bears are in right now.
Yuri Kuma Arashi is a story about Yuri meeting bears and causing a storm.

About the characters:
Yurishiro Ginko CV Arakawa Miho
She's a bear that eats people.
Ikuhara's tastes are reflected in her appearance.
Ikuni is more worried about the silhouette than the details.
He wants the characters to br easy to identify when he makes them an all black silhouette.
There's a secret hidden in the bear hands.
Arakawa was chosen in an audition.
With some of the image of his previous work remainjng, he's asking her to make the character interesting.
She's so eccentric you'll go "Uh?"
There's a mistery hidden in the text of the character image.

Yurisaki Ruru CV Ikuta Yoshiko
She loves honey.
She originated from hearing the opinions of women.
Because a character that women wouldn't like would be bad for this kind of show.
He also worried a lot about the silhouette and let kthers figure out the details.
Especially the contrast between the haircuts and bust sizes were important to distinguish Ruru and Ginko's silhouettes.

When Ikuhara firs saw oppai mousepads he thought they were a great invention, and was jealous that in his works there was no character with big boobs.
He wants an oppai mousepad of one of his characters.
She's the type of girl other girls like.
*this part was still about Ruru, got confused because of the way it was edited*

Tsubaki Kureha
Yamane was selected by audition.
She's a cool person.
Izumino Sumika is both her friend and lover.
Sumika still hasn't been revealed but she's the director's favorite character.
Producer: "Just wait to see her casting."

About yuri anime:
Ikuhara: "I know I'm a beginner in this genre and can't compare to people that have been doing it for a long time. But as I worked on it I realized there are plenty of things that aren't being made, and came to think I might be able to do something new with yuri anime."
P:" Yeah, I'm pretty sure there's plenty of yuri elements in your previous shows" (tsukkomi)
Ikuhara: "I think there were few people that realized, when Gundam was first airing, that it was creating a new genre called Real Robot. I expect Yuri Kuma to become this for yuri anime."
Kureha's mother having been killed by a bear is an important element in the story.
Other than the two bears and two humans, other important yuri characters and bear characters will appear.
Suwabe's character, and the existance of the shotas is a secret.
This is a world of yuri and bears only and men don't appear.

For the main cast, he focused on the difference between their voices.
If you put together a lot of cute voices Cute Voice Inflation happens and it becomes hard to tell the difference.
About Yuri Kuma Arashi:
Producer: "it's an anime that, like the CTU where Jack Bauer works on in 24, has that western TV series element of "anybody can be guilty". It's an Ikuhara yuri series with new elements in it."

Ikuhara: "Often you try to match the work to what's happening but when you get to making it the airing is postponed.
It's important to see what's in vogue right now, but expressing what I want and getting the viewer to think "Why was this made right now?" "Why express this at this time?" Is what I want to do with this work."