AdmiralKosh
Will there be at any point a market where upgrades, ships, etc etc will be sold for real money?
No. Things on the market can cost any in-game resource, usually Essence. Never money. While it is true you can buy Essence, you also get it by simply playing the game, there are no ''pay-gates''.
AdmiralKosh
Or better yet, is there any intention of creating a system where your performance is determined by the ammount of money you can spend?
Absolutely not. While spending money on Essence will obviously give you the advantage of having more Essence, that does not automatically mean you will be better at the game. See why below.
AdmiralKosh
I ask this because this is a trend these days and I think it ruins many great games. A subscription system works much better IMHO.
I agree that it ruins many games when they become pay-to-win or features are locked behind pay-gates. An optional subscription model might be something we look into in the future. But if it ever happens, it will be just that, optional.
Now, to explain some things about the market. Essence is the only thing you can buy for real money, you also get Essence by doing pretty much anything in-game.
Ship parts are cosmetic only modifications to your ship types, they do not alter the ship behavior in any way. You can find ship parts/packs by exploring in-game and once you find a part it's unlocked forever, or you can spend some Essence to unlock them all. Again, these are cosmetic only and change no gameplay elements. A ship with 500 guns parts put on it will not do more damage.
Resources and planets are put up by other players for sale and can cost any in-game resource, such as Iron, Power, Currency, Essence, or even Men or Women.
For example a player selling 5'000 Iron for 100 Gold, or something like that.
And finally, the Artifacts. They are powerful items that you socket into your planets. Each planet has a limited number of Artifact slots depending on how built-up the planet is. Each Artifact grants benefits, and sometimes penalties. In most cases these benefits and penalties take the form of percentage modifiers, such as +20% Mining productivity on the planet where it's socketed. A few Artifacts provide set benefits, such as +25 Metal stat to the planet where it's socketed and so on. What this means in practice, is that even if you try to ''Pay to win'' it won't work, you need the infrastructure to actually take advantage of any benefit. If you produce +1 Iron/minute and get +20% Mining, that will give you a whooping 1.2 Iron/minute. If you've actually played the game for a bit and have an empire set up, maybe you're getting +100 Iron/minute on one of your planets, suddenly getting that +20% makes a bigger difference on your actual production. But at the same time, by that point you have enough Essence saved up from just playing that you do not have to spend money on it. And just like anything else, you can get Artifacts by simply playing the game, without ever visiting the market.
So, tl;dr: You never have to spend money on anything, the balance of the game is on ''Fun'' not ''Make as much cash as possible''. If you like the game I'll gladly accept your money, but you should never feel forced to spend!