I have found that I am able to eliminate my memory leak issue by using ent_purge on a few entities before a level_load.

Using this causes an E1515 error to pop on some occasions. However, in the published version of the game these errors do not pop up.

Is this safe to use, or will it introduce other problems down the line?

Hey dooley, what were these entities that you've purged?

For instance, I have a bunch of stars and planets with while loops that keep them orbiting and rotating. When the player lands on a planet, those objects do not need to be there. When he leaves the planet, the outer space level is re-created and those entities get re-created and assigned anyway.