This is the thread in which we post questions designed to help you get your creativity muscle flexing. Obviously there is no right answer to any of these, but they're here just to give you ideas. These are updated frequently.

How was Quills and Sofas founded?
Which important pony's parents have you not seen yet (canon or in a fan fic)?
The statue in the middle of Ponyville commemorates what?
The Duke and Duchess of Maretonia went to speak with Celestia and Luna about what?
Due to the flexibility of magic in Equestria (Twilight, Discord, Tirek, Celestia, etc.), is there anything that ponies might consider impossible?
What is gryphon culture like? How is it different than Equestrian culture?
How do the crystal ponies feel about non-crystal ponies living among them? How do Cadence and Shining Armor feel about living among crystal ponies? What's the difference between crystal ponies and normal ponies?
What sort of events are held in Ponyville's town hall?
Where are the males of Equestria? Dead? Working? Ponies simply give birth to more fillies than colts? Something else?
Are ponies the superior race? If not, is it Dragons? Gryphons? Diamond dogs? Something else?

3716505 I think I'll give this a shot.

How was Quills and Sofas founded?

Well it all started when the guy realized that quills were in high demand when Twilight Sparkle came into town. The stress of selling so many quills because of one pony nearly got to him. After slouching on a couch on night he realized it needed something else to make it more comfortable. After working on it a bit, he came up with a new sofa idea and decided to sell it. Thus, Quills and Sofas was born.

Which important pony's parents have you not seen yet (canon or in a fan fic)?

I don't read any fics with pony parents, like at all. But I would love to see or know what happened to Fluttershy's parents and Applejack's parents. We have nothing to go on for that.

The statue in the middle of Ponyville commemorates what?

Nothing. It just looks nice.

The Duke and Duchess of Maretonia went to speak with Celestia and Luna about what?

New trade deal. That or plans to attack a neighboring nation.

Due to the flexibility of magic in Equestria (Twilight, Discord, Tirek, Celestia, etc.), is there anything that ponies might consider impossible?

The ponies do consider many things impossible but they do believe that certain ponies are capable of incredible power that can seem god-like. Most are too ignorant to question it anyways.

What is gryphon culture like? How is it different than Equestrian culture?

I got nothing. Don't care enough about gryphons to ask.

How do the crystal ponies feel about non-crystal ponies living among them? How do Cadence and Shining Armor feel about living among crystal ponies? What's the difference between crystal ponies and normal ponies?

Since Cadence is a crystal pony (headcanon) and Shining Armor is not, the crystal ponies accept the non-crystal ponies that live with them. Cadence is a crystal pony so she is with her kind and is the princess of love, so she loves them anyways. Shining Armor loves Cadence and cares for his subjects, so he doesn't care that he is different. I view crystal ponies similar to elves in fantasy worlds. They are that perfect race in many physical terms but ultimately the difference is comparable to the difference between pegasi and bat-ponies.

What sort of events are held in town hall?

They don't hold events at the town hall. They make it a city-wide affair. Otherwise, you have a council of about half a dozen old ponies sitting around trying to remember what they gathered for.

Where are the males of Equestria? Dead? Working? Ponies simply give birth to more fillies than colts? Something else?

There are plenty of males in Equestria. They are just either working or not seen. I blame the animators for not putting in more stallions.

Are ponies the superior race? If not, is it Dragons? Gryphons? Diamond dogs? Something else?

They are not the superior race but they are the most prominent. They control a majority of the world they live on.

3716505
1. How was Quills and Sofas founded?
It started as a writer's shop, selling items related to well, writing. One day a sofa product was offered, which had some type of magic specifically created to help aspiring authors de-stress of even break their creative blocks. Unfortunately, both the sofas and quills were the only items available in the store making a profit, so they scraped everything else and continued to sell only those items (alongside basic sofas)
2. Which important pony's parents have you not seen yet (canon or in a fan fic)?
Fluttershy and Rainbow Dash
3. The statue in the middle of Ponyville commemorates what?
Amity, basically the antithesis of Discord, as she represents the friendship of all that live there.
4. The Duke and Duchess of Maretonia went to speak with Celestia and Luna about what?
About a peace treaty, and potentially an alliance for the next United Nations meeting
5. Due to the flexibility of magic in Equestria (Twilight, Discord, Tirek, Celestia, etc.), is there anything that ponies might consider impossible?
... No, but depending on who you ask, some levels of magic are too immoral to even consider attempting
6. What is gryphon culture like? How is it different than Equestrian culture?
Well, since Season 5 already answer this for me, not much to add here.
7. How do the crystal ponies feel about non-crystal ponies living among them? How do Cadence and Shining Armor feel about living among crystal ponies? What's the difference between crystal ponies and normal ponies?
They are indifferent, but they get along quite well; The crystal ponies are known for their kind and generous ways. Cadance was unsure of her heritage as a princess here, but she's gotten the hang of things and has nothing but love for her people (er, ponies)
8. What sort of events are held in Ponyville's town hall?

In all seriousness, your basic meetings with city workers and employees, and officials, that sort of thing.
9. Where are the males of Equestria? Dead? Working? Ponies simply give birth to more fillies than colts? Something else?
There is a 6-1 ratio of female/male ponies at any given time. It's mostly just a weird phenomenon where fillies are more commonly born.
10. Are ponies the superior race? If not, is it Dragons? Gryphons? Diamond dogs? Something else?
Ponies are the superior species all thorughout the world, rivaled only by penguins, whom they refuse to even acknowledge out of prejudice.

I have really weird headcanon.

1) There's no real big mystery or plot twist here, Davenport just wanted to combine his parents' separate businesses into one unique store.

2) I've pretty much seen everyone's parents in the realm of fanfiction, in canon, however, I've yet to see Fluttershy's, Applejack's, Rainbow Dash's, Celestia's, Luna's, or Scootaloo's, Spike's, or Silver Spoon's parents.

3) That fountain doesn't represent anything important, in fact the only interesting thing about it is that the model for the statue was the great-great-grandmother of Mayor Mare.

4) Renegotiating trade agreements, nothing that isn't otherwise mind-numbingly boring.

5) While many do believe that there are hard and fast limits to what magic can and can't do, it has been proven, time and time again, that, with enough magic, anything is possible. One of the things commonly accepted as impossible is complete resurrection of the dead.

6) I've always imagine the Griffin culture being not too dissimilar to the old Norse cultures of Earth.

7) Considering their shared ancestry, most Crystal Ponies have no problems with non-Crystal Ponies living amongst them, although exceptions do exist for, even here, discrimination and speciesism are not alien concepts, they are, however, even more frowned upon here than in Equestria. Although both do feel home-sickness from time to time, Cadence and Shining Armor are quite happy amongst the Crystal Ponies. While all Ponies can gain a crystal coat, thanks to the magic of the Crystal Kingdom, only the Crystal Ponies can maintain it, thanks to their natural magic.

8) The larger festivals and social gatherings are held in the town hall, as well as weddings, Summer Sun and Serene Solstice Celebrations, and for whenever either of the Princesses decide to visit Ponyville.

9) More fillies than colts are born naturally. The average ration of males to females hovers between the 1/2-1/3 mark, favoring females. In some parts of Equestria, the ration can be 1/5.

10) No one race is superior to another, despite what some may tell you.