It will go against your wish but how about this?
Instead of adding platforms as a loot how about making nauvis chunks into wood(you'd need to find a use for wood eg.coal, oil[Nauvis specific resource], nutrients)/uranium source as that makes sense with unique resources of this planet
Iron chunks being reverted to vanilla recipes thus removing raw metals and uranium from them and changing lava production to take chunks instead.
To compesate for slow earlygame (since this is the only time platforms from chunks would any value) unlock thrusters and basic fuel production from the start or even give the player 1 thruster and 3 chemplants + basic recipes.
On second thought a platform can't fly without a destination so adding a Nauvis orbit location near Nauvis that spawns little to no asteroids that can damage the ship would solve the issue if it required little research or was unlocked from the start. After all the hardest part early on is not platforms but lack of plastic you need for 1500 science to start moving (thruster+planet).
FYI If you want to give one planet from the start Vulcanus is the weakest since once you start moving resources are abundant but circuits, oil, and power are the limit. You could also split Vulcanus(or any planet) research into cheap destination and standard 1000 for the rest after that.