Hello! First of all, I really enjoy your game.
I bought the Ukraine Bundle and it was a pleasant surprise. I play it during my study breaks, I'm an IT and automation engineering student and being able to see my studies applied to a certain degree into your game is quite interesting!
I have some ideas for it:
1. Playable Turrets/Auto-Turrets for defending your base. They can be destroyed by enemy (maybe permanently?) but you can fix them with the toolbox before it's too late.
2. Ranged weapons of any kind, those slugs are a bit annoying to kill in close combat.
3. Automatic gates (normal gates upgraded like the airlock ). They could need to be connected to the power grid in order to operate, and due to the fact they would be automatic, they would not open/close during blackouts.
4. Picking up fruit trees would be great, maybe using the shovel or the drilling machine!
5. An optional minimap on a corner would improve the playability in long terms.
6. A portable lamp you can place outside during mining operations in the night, someting not too powerful. It could be fluorescent (so maybe a crafting combination between radiocative plates and purrtanium plates). It could be timed and after a while you would need to refuel it with another radiocative plate.
7. Thermal reactor, it can be placed on fire geysers, but if another fire geyser is close enough, it can damage and destroy the structure( none or half resources dropped when destroyed)
And that's it, at least for now. If something else comes to my mind, I'll post it here.
Keep up the good work, the game's already nice!