The Treasure Space is the most valuable ability of Zhou Tian's Emperor's Treasure Artifact, and using its ability to deal with the Heavenly Gods he faced was the most suitable choice.
On the surface, Zhou Tian's control over the Treasure Space seemed to lack attack power. Thus, by using only the Treasure Space, Zhou Tian could at best trap those Heavenly Gods, but if he wanted to slay them, even with his strength, it would still be somewhat challenging.
In reality, Zhou Tian just needed to use the ability of his Emperor's Treasure Artifact to bring those Heavenly Gods into the Treasure Space. Even if the Treasure Space itself lacked attack power, as long as Zhou Tian could use the space's ability to bring enemies into it, dealing with the Heavenly Gods would then pose no difficulty from any perspective.
