After discussing with Phil about the possibility of a character based project, he said yes to me doing one that could eventually be used to pitch a tv show, and yes to have a group of characters centred around space.
He did, however, say that I needed to answer some questions to solidify my idea so that it could be used to sustain 12+ episodes of a season.
An environment that would sustain episodes
All tv shows have a place where characters are set. It allows for people to live there and live their lives, while also allowing for things to happen to that environment as time passes by in seasons. The environment of a show concept must be almost first and foremost, even just thinking of what the environment could be will help to build characters for it. You can't make the characters first and then throw them in. The environment comes first, and the characters will follow.
Shows like Steven Universe have set environments. One being beach city, the other being the temple where Steven lives. Only recently have they expanded those environments to the "Homeworld" where all gemkind live.
Other shows like Voltron have a myriad of environments to use like the different planets they save, but they still have their main one where they hang out. Which is the castle turned ship.
Thinking about a place to set this space adventure in was simple enough. Anything big like a school or space station would be perfect since people would always be coming through. Plenty of space for a main group and secondary characters to enhance a cast. Though I'm thinking of a training school for astronauts and space adventurers. The characters could be training there and all of a sudden be thrust into an adventure when something goes awry.
Other environments could be different planets. The group could be going there on adventures and there would always be secondary characters on those too.
The environment must have a backstory/history and a set of rules
The environment the characters are set in must have a kind of history. Like our world has our history of wars and evolution, so do imaginary worlds like RWBY and Avatar: The Last Airbender.
RWBYs history of The World of Remnant is complicated and still hasn't been explained fully (though its getting there) in their Six seasons of the show and 3 seasons of World Building episodes. The main gist of it is that in the past there were 2 brothers, gods that lived on earth and gifted mankind with magic. When mankind displeased them, they took away that magic, leaving them with dust. Stones infused with magic that can be harnessed by mankind. Dust can be used by everyone and is an open resource. However, the gods also left mankind with 4 relics, that when bought together could summon the gods back and allow humankind to be judged. Evil forces known as Grimm are drawn to them to destroy them, and so humankind built academies to train humans to fight the Grimm and to protect without them ever knowing the relics existing.
The set of rules that encompass the world of RWBY is much more simple. Every character must be based loosely off a fairytale, story or myth/legend. Ruby has red riding hoods Cape, Blake reads books like Belle and has a counterpart Adam who is based off the Beast loosely. The characters also must have names that are based off, or resemble a colour. Blake is Black, Weiss is White in German, etc. There are also teams in RWBY that must be based on colours as well and only consist of four people. The team RWBY consists of Ruby, Weiss, Blake and Yang. The four main characters. One more rule is that the characters must have a semblance. A semblance is a unique power that characters have. Weiss can summon glyphs and Blake can use "shadows" to help her be unharmed.
Though I haven't begun thinking of a backstory and backstory to the world I hope to create, I am aware it needs to happen and am hoping it will blossom as I go forward in premise. Especially since coming up with these histories and rules are complicated and need to fit together.
What's already in Culture relating to your subject
On the theme of space, there is a multitude of things in popular culture. Ranging from cartoons to horror films. In terms of cartoons and tv shows, which is what I will be focusing on, there are Voltron, She-Ra, Steven Universe and Sailor Moon (and most magical girl shows feature extraterrestrial influence) are some just to name a few.
The challenge for me is bringing something unique to the table that hasn't been linked up with Space before. Or something that has been done, but in a different way than others. Therefore I'm thinking of going with a retro theme and influence with my designs, but still keeping "modern" aspects of that makes space shows what they are, Futuristic.
In terms of diversity, it doesn't make sense to just have the "gay team" just for the sake of diversity. If someone is gay, or trans etc it needs to come up in the show as naturally as any straight relationship would. For example in RWBYs latest episode, it was revealed during a fight (and after several long months of friendship) that two characters Yang and Blake like each other more than just friends, and that they love and protect each other more like a couple. It came up because throughout the previous 3 seasons their friendship was tested and strained and the more they talked the more they realised their feelings. It isn't the overarching plot of RWBY, but it was relevant for that story arc of them reconciling their friendship.