I have been working on a game for several years on and off (everyone's development speed is very different)
From reading a ton of guides for both this project and some others, If found that, for me at least, it was easier to start with a question rather than an answer. If helps me and some others stay organized with a clear goal in mind first.
I do no know where you particularly are, so forgive me if you already have this done.
I like to Have some base questions and have answers for them. Why am I making this? Who is this for? What type of players will be interested or use this game? What do I want the players to get out of this?
Then I start asking How I plan on entertaining those types of players and how I plan on keeping them engaged and how or what part of the game will achieve why I want to make it in the first place.
Some seem to jump on an idea before considering why they want it or what it would be for or what problems it may solve. Or even what about it will be new.
I didn't do this before but I also am finding it helpful to make and plan out a time line of goals for the development of the ideas and concepts and how long each should take. Like finalizing and creating a string of events and features, what mechanics you want, and so on. It depends on your preferences and abilities and what you have access to it seems.
But that I just stuff I learned and think I understand. I'm sure most is just from my engineering classes over the business courses I took. Engineering taught me to get in a habit of finding a problem I want to address first and then find answers for it and then development and prototype/test my ideas.
Teams seem to come form anywhere, willing or able friends, family, volunteer, paid. Paid seems to be the easiest and most sure fire way for quality. I have no idea if it's right, but I'm starting with planning out visuals, sneak peaks, and explanations on what the game i'm working on's goal is along with planned features to post over time to get people hyped and know i'm serious so they maybe more willing to contribute to the future kick stater. But right now i'm still planning what I would want to show off to the public, what i want in production behind the scenes and about how much starting out of pocket money i'd need for that self advertisement so i can get enough interest to get enough donations to actually produce the full game and launch it.
Again I'm just spit balling here. I have no business experience. This is just stuff I picked up on from classes and guides and asking. And of course I left out a tone of micro details so i don't send a novel of things I learned from guides and videos and such.
I feel there are several ways to go about the development, this is just one possible, and vague, path of action.
But do feel it is important to at least consider those questions at some point since you probably will be asked them by your potential development team I'd assume.
However based on your comments, I would suggest that you begin this way.