@Trötter Dämmerung  
Kind of wonder if there was anything for Luna since Tabitha also voiced her?

@Trötter Dämmerung  
I just read Jim Miller’s posts about what each voice actor’s ideas were.  
I’m surprised Ashleigh Ball wanted to put Rainbow Dash with Zephyr Breeze.

@Red-Supernova  
First of all, they were credited for story ideas and not the actual writing, so don’t expect to see full scripts from any of them (except Tabitha; She often writes scripts for the cast-reading panels for conventions where she’s a Guest).  
That said, TVTropes states that the story ideas were: Rarity plotting a heist, Fluttershy being a spy, Pinkie Pie going to space, Applejack leading a secret life as a country western singer, Rainbow Dash encountering Zephyr Breeze, Spike having a Lilo and Nani relationship with Twilight, and Twilight having a sibling rivalry with Shining Armor.

@chris the lovable jerk  
Sounds like it could have been, but got nixed because it was essentially her Cutie Chronicles story with a different reason for leaving the farm.  
Plus, in my opinion, it’s funnier to have everyone wondering if she just made the whole thing up, made it up ages ago, or was actually real.

I can’t believe all the main leads wrote this one. But now I want to know which parts each of them wrote.

@chris the lovable jerk  

I swear I remember an interview or question event years ago where she mentioned wanting to have Applejack as a country western singer in some capacity. I think it was in response to the exact same kind of question that prompted this episode, i.e., what the VAs would like to see their characters do.

@Background Pony #DB93  
Cue the entire staff apart from Cathy rolling around on the floor laughing hysterically.

@Background Pony #878B  
Writers: So what kind of role do you want Spike to have in this episode, Cathy?  
Cathy: How about one where he is actually fucking respected for once?

I can imagine the pitch meeting being along the lines of:
 
Haber: So, does anyone want add anything?
 
Weseluck: Yeah… oh, yeah. For the last eight years I’ve been beseeched by Spike fans begging for any evidence taht Spike was part of Twilight’s life when he was a baby, or any information about if he and Shining interacted when Spike was a child, or if Spike even knows Twilight’s parents. Can’t I add something about that, please?
 
Dubuc: Include something about Spike? I don’t think we have time in the episode for him to mess anything up…
 
Haber: I don’t know. Tara, what do you think?
 
Strong (sipping bourbon in an oversized chair at the darkened, far end of the table): ’Kay…
 
Weseluck: Oh thank God…

@CaptainGrumpy  
IKR for the first time in 8 years

I really hate it when they change the title of an episode at last minute.
 
Makes it confusing.

damn the entire cast wrote this? they’re really going all out on this final season aren’t they

@chris the lovable jerk  
I know the whole Pinkie Pie moonwalking on Saturn was all Libman.

I’m honestly wondering if the Apple Core story was an episode idea that Ashleigh pitched and they never found a place for it until now.

The five voice actor are story by nice