star wars - What happens to the universe if the Force gets too out-of-balance?

What exactly happens if the Jedi just leave the Force to the Sith?

I can think of plenty of political consequences - the Sith take political control of the galaxy, build an army, and have an empire of their own. In other words, the consequences have very little to do with Light/Dark balance of the force.

However, while that's happening, the Force is probably going to tilt more and more towards the dark. What I'm curious about is - what are the consequences of that?

Now, I am certainly imaginative enough to think of answers like "things start dying everywhere." But are there any canon examples/descriptions of Force imbalance consequences for which we can't directly blame some Sith and his/her hunger for power? Or is there at least any indication that the Jedi's obsession with balance is something more than dogma?

Answer

War would intensify and the Sith (and likely other dark-siders as well) would gain strength.

We know this from to the Star Wars: The Clones Wars episode Alter of Mortis.

On Mortis, there were three beings, The Son, who embodied the Dark Side, The Daughter, who embodied the Light Side and The Father, who embodied balance. Eventually, the Daughter died, and the Force became unbalanced. All of Mortis immediately became dark,

and The Father says this:

The balance has been broken... As the balance in this world crumbles, so shall war escalate in your galaxy. As my son has descended into the dark side, so have the Sith gained strength.

Eventually,

The Son is killed, and balance returns.