Recently, We've had some problems in the end world with people (intentionally, or not) building near/on other peoples stuff, screwing the spawn rates of grinders in the end world.
I'm going to offer a short and simple solution to this.
a. On the main island, the same Kreatious rule applies, structures must be 20-25 blocks away from each other, and must not interfere.
b. When outreached(via bridge) from the main land, all structures must be at least 180 blocks away, to prevent deterioration of spawn rates.
c. Possible piston cap to as to how many can be placed in a certain area, to prevent lag and spawn hoarding.