A lot of text, but i want to try to help with this game, its not hopeless.
I am guy who like shooters, i played it a lot (~10 000 hours played from 2008 for now on ps3 and ps4). I played a lot of different games (Resistance 1,2,3, battlefield bad company 1,2, Battlefield 3,4, Killzone 3, Destiny 1, including many free2play games Dust514, Planetside 2, Blacklight retribution, Loadout, Fortnite, H1Z1 Royal battle, World of Tanks (its, dare to say, some kind of shooter too).
So, i want to say, i know shooters well. And i am old enough to make some analisys. And yes, english is not my native, so dont take my mistakes in it too seriously, try to take what i mean.
My post addressed to developers, i dont care about opinions of players.
I like concept of game, its interesting enough, but game will not become popular if devs wont understand what they do wrong.
I waste my time to write it as experiment, i doubt if any devs will read it and take it seriously (they usually have too high opinion about themselves and their sacred plans about evolution of game), but i want to try.
Now what i want to say about free2play games and about that game in general.
I saw 2 ways of evolution of free2play games:
1. Explosive burst of popularity - World of Tank, Fortnite
2. Balance near death line of numbers of online players - any others free2play game (sometimes they near death from beginning, sometimes they lost their players because mistakes in development choices)
So. This game obviously not going to be 1 way of popularity.
And here we are to try to undertand why free2play games lost their players. I will say it from point of view of competetive player.
1. Bugs, unbalance and netcode problems.
This game have good enough quality about bug and netcode. But characters is unbalanced. Unbalancing usually not problem at all, if game is interesting, most people can wait fixes of balance.
2. Lack of content. Lack of goals.
For start of game here is enough of missions. But for me here is obvious lack of goals after 2-3 hours of playing. You can set as goals - unlocking characters and weapons only. Ok, for some time its work, because of curiosity of players, and some players just like to try hard to collectioning things (i dont understand them, but they exist and here are many of them). But any player can make some approximation - i got new character, and new weapon... for what? What i will do with it? Why i must spent time (a lot of time in this game) to get new one? And answers for Spacelords is not positive for developers - answer is - to do the same, what i did 100th times before it. And when player will get this answer - he most likely will leave this game. I almost deleted this game, because of it, only one thing stopped me from that action, i will write about it further.
Characters and weapons should be resource to play the game. Game must give the goals, where characters and weapons is just tools. For now you can get tools to get other tools. Its seems pointless for anyone, who can think in one step to future at least.
Btw, same thing happens with planetside2. When fun from new experince is over - player suddenly discover - game dont have other goals instead collecting of weapons. And players leave it.
So most free2play games (especially unpopular) usually do same thing:
Make game with unique feature (massive battles in planetside 2, or "wallhacking" helmet instead of minimap in Blacklight retribution, and Antagonist in Spacelords) - and think it will work forever for attracting new players. It wont work in long perspective, any new experience lost its newness fast or very fast. And if devs have nothing more to provide for players - game die or balance near death.
How to solve this problem? Its hard enough, but i guess is possible.
Basically your game is same as Destiny with only unique feature - Antagonist. But Destiny contain not only PvE, but also its contain PvP, and they do a lot of activities to hold players in the game. Your Spacelords contain only PvE, your Antagonist feature - is not make it real PvP. And playing same missions hundred of times is boring for both sides.
Even Bungie have not many resources to create new PvE content fast enough to satisfy players, so they do activities, challenges and etc. Not enough, and their PvP system is bad, its have same lack of goals, no clan system, no clan battles, no true competetive.
When player play PvP game - he like to compete with other players. What its mean? Its mean he is like to compare his skill with skill of other player. Its one part of it. Other - here a lot of people, its impossible to play against everyone to compare with them. So, smart people figured, we need to make statistics of players, and rating of players. so each player can see his own statistics (accuracy, % of headshots, KD, WL, MMR) share it with anyone, and bragging it, or shame it, and try hard to improve it.
So making new content ( i mean new missions only, making skins or weapons - is pointless, if you do only that) - its not primary goal for devs. Because its dead lock in long terms.
Devs must make new gameplay experience in existing content. Like improve PvP system, make statistics, site where we can watch it, make new PvP modes, 2vs2, 4vs4 and more. Make rating of Antagonists, Mercenaries in public sites and etc. Also new PvE activities, like "hold waves of enemies" and etc.
And devs should do it first, they have no time to lazy creating new weapons and skins. Players will leave this game before it, here nothing to do.
I am totally bored while writing this post. So its over.
And here only reason why i not deleted this game - you make this game without aimassist (thanks for you), and i keep it as "training apparatus" to keep my aiming skill up. So i play as Harec only, and do headshots, when i have no friend online to play other games, where devs make goals instead of endless collecting weapons.