This is a really cool take on the idea of Lavos versus the Entity... But how would that work, do you think? It's pretty clear that: (1) the Entity is somehow the planet itself and values life, and (2) Lavos is literally a destroyer in that we see he destroys 65 million BC (and wipes out all life on the planet), he destroys Zeal and most of the world in the Antiquity, and destroys the world yet again in 1999AD.
Not disagreeing, I think this is interesting. But I'm wondering how it could be spun that Lavos wasn't actually the bad guy in all this.
First off, I'd like to introduce the idea that the entity has a physical embodiment, and possibly shares the same spirit/thoughts as the planet, like a deity.
I'd like to think that Lavos had some other interactions with the entity outside our limited vision (being tunneled to strictly viewing generally what our party experienced)
ie: in 1999AD the entity had infected much of the planet, OR has gathered an army of some sort, and the only solution Lavos fathomed was to wreak havoc and destroy all (much like a Noah's arc type situation)
In the destruction of Zeal, simply put: They were sucking Lavos' energy... draining its life force.
65mill BC was most likely when Lavos first detected the entity and calculated that wiping out the minimal life that was existing on the planet was well worth the small sacrifice to destroy a larger evil.