The game looks great so far! I do have a share of praises and criticisms:
++The DNA/Shooting mechanic is fantastic, it rewards you for killing enemies while also incentivizing you to kill instead of just running away.
++The camera controls are amazing for this type of game, most modern metroidvanias suffer from the lack of vertical awareness, but these controls are definitely a great solution to the problem.
++The boss battle's expertly designed. They are a true test of the players skill and are fun to fight.
+I really like the jetpack mechanic, the lack of jumping is weird but with time it becomes tolerable. I think the control limitation you've given will allow you to be more creative with certain aspects of the final product. However, I'd recommend writing in a reason for the lack of jumping as to not confuse players. Maybe make the excuse that the protagonists armor is too heavy?
-+ The long journal logs will definitely alienate some players, so if you want to avoid that, try to make the mandatory ones more concise without breaking the suspension of disbelief.
-+ The enemies are kinda hard to see when they're not moving, I'd recommend doing something to rectify this but this is a matter of preference.
-+ Standing still and then going left/right is jarring, I'd personally recommend that the protagonist starts slow for 1-2 frames and gets up to full speed by the 4-5th frame in animation. Same with turning around. This may conflict with the game design, so if it's too late to fix/change, I completely understand. It's not that important, and again, a matter of preference.
-There's no good reason as to why the protagonist should stop the game and make an entry log about something that we, the player, are witnessing ourselves. If you want to keep this for some reason, here's a possible solution: Every time you explore a world and see something worth writing down in an entry log, notify the player by flashing "log updated" on the screen, and then allow them to access the logs via when you leave the planet. This will not only give us an insight into the protagonist's personality, but it will also be a handy tool for gauging how what the player has done on the planet, giving them a hint as to what they can do next.
-When the player falls a certain distance, they take falling damage. This is fine. However, there's a point where the protagonist falls through the floor in a cavern while escaping the planet, and when he lands, he doesn't take falling damage at all. This may be considered "nitpicking," but I think consistency between gameplay and story is important.
--I genuinely hope the music is a placeholder, because not only does it hurt my ears and gives me a headache, it never compliments the tone of the game. There's two key problems with it: 1) Nobody likes Midi when it's painfully obvious that it's midi. 2) Classical, or traditional, music doesn't belong in a game where you explore new and distant worlds. Music direction like that is meant to give a sense of nostalgia or belonging, something you're not supposed to feel in the depths of alien worlds infested with dangerous monsters. If, during world exploration, you wanted to make the player feel afraid, you failed completely for me.
--The destructible environment doesn't really add anything to the level design and generally makes the game more tedious to play. They make the levels look uglier/less consistent, and that's really the only way you can separate them from normal terrain. That being said, there was one decent use of it where, if I didn't destroy the blocks, I could access some extra resources. Though, that doesn't make up for the rest of the issues with it.
As for bugs, I personally didn't find any.
All this aside, it's a very fun, creative, and ambitious game. I can't wait to play the final version!