Liberals: In its purest form, do you think a laissez-faire economy would be the most ideal?

Absolutely not. In it's truest, purest form, laissez-faire is FEUDALISM, and there is nothing good about that. The middle class is a construct that is created by market regulation. It does not, and never has existed without heavy regulation. The less regulation, the bigger the divide between rich and poor, or "lords" and "serfs."