In my humble opinion, you should try to think hard about what you want the game to be
exactly about (or tell us if you have decided about it already

).
I see a lot of vague concepts being thrown together for good measure, but very little in terms of a clear direction for the game. Designing and working out lots of things at once might be overwhelming in the long run, unless you have a very strong vision for the project right from the get go and lots of experience making games (and even then, it might still cause issues).
Please, do not think I'm being harsh or anything. I just think you might want to focus and define a good and solid core for your game, especially since it's your first 'serious' indie project. They say it is much simpler (and time-efficient) when you define and flesh out a very limited but clear scope for a game idea, even if that means you end up adding stuff or even dramatically changing your initial concept at a later date.
You might want to make your mind about simple stuff like:
- What's the the player's purpose/goal? (save the princess, retrieve yendor, etc.)
- What are the
main game mechanics the game will be about? (hint: the less and the simpler the better. Better focus on a few core mechanics first, you will always be able to add more later on as you see fit)
- What kind of challenges the player needs to face and ultimately overcome? Is the player opposing a specific bad due or faction? Is the player just opposing the environment (and its denizens)?
- I get you have already considered lose conditions. How does the player win the game? Can the game be won at all? If that's the case, how? If the game cannot be beaten, does the player have any strong incentive pushing him to play the game indefinitely?
That's only one of many approaches, but the main point here is trying to establish a very clear core experience for the game, in order for you to be able to develop for and iterate over it in a more agile fashion.
For instance, you might want to cut on any feature which aren't absolutely necessary to fully appreciate the core of your game. As an example, you might want to completely ignore weather, day/night cycles and all that good jazz, at least at in the prototyping stage, if those don't have a key role in how the game works at its most basic level.
If weather only influences combat and other things by altering a few variables to some neglectable degree only, then don't bother with it until the core of the game is solid enough. As a counter-example, the lighting system in
Chroma end up playing a crucial role in how its gameplay works.
- Mock-ups and quick and dirty prototypes might still be a good way to get a feeling of how you want different things to look and work in the game. But as long as coding-in new features and producing assets go, stick to what's most important first. -
Focus on what's absolutely important for your game, add the rest later. If you think a lot of different elements all equally play a role in Isomer, find ways to cut those down and have the game focus on only a few of them instead. Design by subtraction first, add more stuff in later on.
You might very well just ignore all of this nonsense, or maybe I'm just offending your intelligence cause of lack of knowledge about you and the project on my side. If that's the case, I beg your pardon in advance!
Cheers and good work
