The Ring of Sauron

[the phantom]

If it were not for the Ring, his body probably would never have even been destroyed.

What do you mean? There's no such thing as an indestructable body. How would not having a ring have kept his body intact at Numenor's destruction? Trust me, when a body is crushed beneath the sea along with an entire island the body definitely gets destroyed, ring or not (and having the ring allowed him to return).

Or are you trying to say that if he never would've made the ring that he would've made sure and not become incarnate?

But is it really possible for someone so focused on domination and mastery of the world to avoid becoming incarnate? His master (Morgoth) couldn't avoid it. He became tied to his physical form (but Morgoth also had an anchor so he could survive the destruction of his body).

No, Sauron spent too much time interacting with and attempting to subject the physical world to not eventually become incarnate.

It seems to me that creating an anchor was the only way he could continue to come back time after time.