This is surprising how I randomly find it by just using Google, but... actually, after reading I have what to say.
First of all: lore and world in the game. Developer of this game is from Russia (I'm an Ukrainian) and he once said that he orthodoxian who really believe in God. And of course that's shows up in some parts of game. This is like Stalker or Metro: you can play the game but there is something what can understand only a true member of slavic culture. Romani Empire is a reference to Russian Empire in times of Alexander II Romanov (here is why Romani not a reference to Rome but for Romanov dynasty). Shown world for me looking like reference to Afghanistan with all this multicultural nations and differences in seeing a Romani dominance over Herat. So to understand this game totally you must be familiar with slavic culture and history.
And also I had been shocked when I saw here comparing SS and HF. This is very different games. HF more like submarine sims. If you played Silent Hunter, Dangerous Waters, UBOAT, Cold Waters, etc, you can easily see some kind of similarity. Economic system here compared to UBOAT, global map more like simplified Dangerous Waters gameplay. All this game looking simplified in comparation to other game. Look into shipyard onto the parts for building your ship. You have few variants of light guns, few variants of heavy guns, one rocket, few strategical rockets, two planes and... that's all? Look on the interface. Everything just fits on one screen: passive and active reconnaissance, rocket and planes launching interface, radio-interception stuff, etc, it's all fitted on your screen and accessible in few clicks. If you look on Dangerous Waters – there are so much buttons to push and so much stuff to use. Mechanics? Yeah, if your radar find something, you don't have a nice marker on map unless you draw it by yourself. But do you at least once count a distance between two points and, using time what passed between it, count speed and approximately point of your rocket/fleet/planes intercept this contact? Of course no! You can, yeah, but any sense? Your planes/rocket find target by itself, your fleet can be controlled, so there is just no point for that.
Fights really close to SS but not so. Of course they're simplified: not so much mechanics, not so much difference in weapons and ships and more and more and more... Much people hate aiming arrow. Well, how do you think game can be with good crosshair? But with this arrow fights feel so adrenaline and epic when you trying to shoot your enemy and avoid those missiles. This is just a reasonable part of game design and I totally agree with it. I can explain battles in HF like moving from newest aircarrier/cruiser/destroyer to WWII battleship. It's old and rusty, it's weapons incomparable with high-tech rockets, guns and planes. But when you, after listening ASMR loading of your 180mm guns on "Sevastopol", shoot a whole pack of "gifts" into a unprotected part of their heavy cruiser, you receive so much adrenaline and satisfaction that can't be received from any from those modern toys. Also this gameplay reminds me those old simple casual games where gameplay based on simple action itself not on the rich mechanics.
So summary what we get:
+ atmospheric game with dozens of small highly-cultural things things
+ good combination of simulation parts and casual gameplay
+ some hardcore on hard difficulty
+ lore what comes not from direct speech but from short parts of dialogs
+ pretty interesting story like for me (yeah, it's not gorgeous but I was intrigued at some points)
+ good bunch of "diplomatic" mechanics
- not so deep diplomacy (can be better with all those invented mechanics)
- some mechanics just missing like ground forces or crew management
- cities are to faceless (they have literally no difference)
- not so many hard-to-achieve easter eggs (and they're not influencing a storyline)
So for one dev this game is pretty good and perspective project. And it mustn't be compared to SS or treated like clone or something. It is self-sufficient enough on my opinion. And I wish dev to make a sequel and improve his game.