Ok, I read the player reviews, and I have a few more thoughts:
(1) The people who praise the game specifically flag the "hard scifi" aspect. You don't mention that anywhere on the page. I think you should reconsider.
(2) The blurb opens by calling it an isometric RPG. The only screenshot that even arguably looks like an isometric RPG is the second to last, but that looks more like a sim/basebuilding game to me. The other screenshots look like: (i) first-person game of some sort; (ii) first-person game of some sort; (iii) 4X game; (iv) X-Com or 4X game; (v) adventure game?; (vi) ???; (vii) ???; (viii) as noted, sim/basebuilding; (ix) first-person game of some sort. In the video, only :54 to :58 look remotely like an isometric RPG. (I won't try to define every other second, no time to waste on that.) I think you need to consider whether you want to market it as something other than an isometric RPG, or whether you want to change your visual marketing, but right now there seems to be a big disconnect.
(3) The reviews indicate that there is extremely diverse gameplay, but nothing in the marketing text conveys that at all. The blurb says it's an isometric RPG; the long description is just about story. The only thing to suggest that there's anything non-RPG about it (I'm talking about the text) are the references to harvesting resources.
I think you need to figure out who is going to actually like your gameplay and target them. The isometric RPG crowd strikes me as overwhelmingly interested in character-driven stories and tactical combat. It's not clear that your game offers either, so I don't know if that's the right thing to emphasize. There is a strong niche for hard scifi, so that would seem a market to go after. There's also a market for base-building (e.g., Rimworld). I don't know. I'd try to figure out your player base, repackage the description and visuals to target that more directly.
Here's what AOD's blurb is:
The Age of Decadence is a turn-based, hardcore role-playing game set in a low magic, post-apocalyptic fantasy world. The game features a detailed skill-based character system, multiple skill-based ways to handle quests, choices & consequences, and extensive dialogue trees.
I've bolded all the things that target certain niches of players that I am confident exist and overlap.
Here's your blurb:
Titan Outpost is an isometric, single-player role-playing game set on Titan, the sixth moon of the planet Saturn. Humanity is engulfed in an energy crisis and it's up to you to harvest the moon’s precious resources and uncover its mysteries.
I've bolded what are serving as your niche items. I don't think there's a strong "Titan" niche to market to. I don't think the "energy crisis" crowd is interested in hard core RPGs. Not knowing much about your game, here's a proposed rewrite:
Titan Outpost is a hard science fiction role-playing game in which you must build a base, manage its crew, develop your character's skills and attributes, and explore Saturn's seventh moon, uncovering its mysteries and harvesting its resources.
This conveys more of the gameplay (assuming I'm right) and drops facets that I think are not likely to attract players. Then I would restructure the long description. AOD provides one model. Another way would be something like:
It is the year 2077. Earth is slowly dying and starving for energy, and humanity has turned to the solar system to meet its ever-growing needs. The Moon has been plundered; the Chinese have begun to colonise Mars, and now the world has set its eyes on hydrocarbon-rich Titan, Saturn's seventh moon. Your employers, the International Autonomous Space Association, are desperate to claim it before the Chinese can. On frosty Titan, this war will be very cold indeed. [Shortened narrative down to a single paragrah]
Key Features:
* A hard science fiction setting inspired by Robert Heinlein, Arthur C. Clark, and Stanislaw Lem. [or whatever]
* An open-ended structure in which your choices define not only the course of the plot, but the fate of the world.
* A rich character-creation system, in which you define your character's attributes and develop his or her skills and gear over the course of the game.
* A robust base-building system, in which you must manage your crew, resources, and facilities to survive the harsh environment and your political rivals.
* Multiple approaches to the game's challenges: dialogue; crafting; exploration; trade; and combat are all viable ways to win.
* A rich and reactivity story full of mysteries, twists, and memorable characters.
I have no idea if that's true, but something like that would, I think, do a much better job of telling people why they should play your game.
(4) I think the $25 price point is the wrong price. I would drop to $19.99 or even $9.99.