About collisions, I can notice how Icaras hits the environment without actually hitting it,
same for AG-Systems (front of the ship), so that's made me realize there wasn't
any real collision but an approximation with another model, which is standard way
in games anyway, because it's a lot faster to process.

And it's good because that way, every ship design is good, no disadvantages if the ship
is bigger than another, but damn it's bad when I see my ship hitting/scraping the wall
without any real collision!
And the gitch darkfaeraytales is talking about (ship sinking into the track) probably
comes from this as well.