The game is extremely... hollow. Everything you can do in the game is just improve some parameter or other. I felt absolutely no immersion. All resources are just bonuses to gold/science/food/production, as are all improvements and technologies.
Interface is, frankly, horrible. The game piles on tons of options without giving an easy way of orienting in them. The worst offender is by far the improvement screen. Not only the game doesn't hide stuff that simply cannot work (i.e. +2 capacity on tiny and +1 on small planets in a system with only medium and larger planets), it forces you to manually check which bonuses from improvements coincide with the present planet types. For example, if an improvement gives +1 dust on barrens, deserts and lavas, I have to move my mouse away (because the tooltip obscures the planet descriptions) and check whether I have any of those types. That may not seem like much, but you have to repeat it for every single improvement in every single system. Maybe even multiple times if you forget that a given improvement is pointless in a given system.
Tech tree is crap. At any given moment you have a FUCKTON of availible technologies, most of which take 1-2 turns to research and are as linear as possible. There's not a single tech that, for example, gives new weapon technology AND an economical advantage. If you need exploration, you go down. If you need military, you go up. Needless to say, those directions never cross. Additionally, there's no way to see which technology gives you what you need. I spent like 20 minutes looking over EVERY SINGLE FUCKING TECHNOLOGY to see which one gives more 'command points'. Because obviously getting more than 5 ships together requires some kind of Overmind.
AI is primitive as fuck. The pirates are overpowered as fuck. I played around 100 turns and 80 of those I was forced to chase pirates around my systems. Battle interface is crap. It is dull, slow, but when you want to wait and see what your cards do, there's no pause option. It's just 'sit and watch pieces of metal shoot shit at each other'. By far the worst element of battles is the inability to form a fleet and assign a commander before taking off from the hangar. Have a pirate horde invading your system which has your fleet in orbit? Sorry, no way to assign it a commander. Fuck you, player.
And last but not least, the amount of technobabble just melts my eyeballs. The designers had some kind of obsession with antimatter, judging by how they put it EVERYWHERE. Void stone? Antimatter inside. Weapons? Use antimatter. Antimatter? Fucking mined on planets. And about 5% of sentences in the game use a wrong tense.