Factorio Forums

I know this may not be too big of an issue, but I find that you need petroleum a lot more than heavy or light oil in mid game. I feels more like a boundary than a challenge.

Thing about it- you need petroleum for sulfur which you need for sulfuric acid but the only thing you can do with the oils is turn them into fuel.

It may just be me, but I feel like the oils are unbalanced.

Just one step further in the science tree, you have advanced oil processing, which helps you choose what proportion of petroleum/light/heavy oil you get.
Thus, the imbalance in needs doesn't translate into "I will forever have too much of an output, and not enough of the others".

If you're relatively quick with getting blue science set up as soon as you finish your first refinery, you can place 1-2 tanks for light and heavy oil and have cracking researched long before they fill up.

In the end you will be cracking all kinds of oils into petroleum gas.
Before you can research Advanced Oil Processing you can just fill some tanks with heavy/light oil or even process heavy to lubricant and light (optionally heavy as well) to solid fuel to use in your power plant or furnaces.
After the research you can balance all oils to your needs by using circuit networks and pumps.