Balancing exponential upgrade progression

I am using an exponential upgrading system for a game I’m making. My issue is that I can’t find a good way to balance the system. The initial few upgrades are extremely steep, and they get progressively less steep as time goes on. If I raise the initial value (6) to the power of the level, the progression becomes too quick.

This is the current equation I’m using:

value = 6*math.pow(level, 3)

Any suggestions on how to balance progression would be extremely useful.

  1. Implement incremental increases: For example, you could modify your equation to value = 6 * level^3 + 10 * level, where the linear term adds a constant increment to the value at each level.

Adding an incremental increase would still be insignificant.

Ideally, the progress would look something like:
image

If I raise the initial value to the power of the level it becomes to steep at later levels:
image

With your solution and my solution it’s not steep enough at later levels:
image

What is the formula’s result do? Is it like a price to the next upgrade?

You can use desmos as a way to test different graphs at different values to see what you like.