"I think, planets and asteroids must have vary parameter of gravity for transporting differences. "
I thought the same thing when I first implemented gravity. The game already allows for different gravity per planet but it was not fun to play. It makes the game inconsistent, confusing, and sometimes even annoying. Maybe it will be used on special bosses only if it feels okay.
"Not only replicons, lava and acid drops is enemy (in addition to knocking myself to death)."
Agreed. I'm now adding lots of new content and the latest build already has new dangers. There's a plant that spits seeds that bounce around and explode. There's also a cactus that explodes it's spikes everywhere. Some objects are also now radioactive. Expect plenty more hazards like these in the final game.
"Maybe weather conditions too"
I've been thinking about weather recently. Maybe acid rain or radioactive weather. It's something I'd like to add if there is time.
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Thanks for the ideas, keep them coming.