recommendations for challenging cycle classes

Edit to simplify: Which 45 min AF+ cycle classes have you found to be the most challenging?

Having taken, and taught, indoor cycle for many years, I find the AF+ classes to be too easy with too many breaks. Yes, I am in control of resistance and can always go "off script" to make the classes harder. However, would prefer to let my brain "shut off" and follow along.

Any recommendations for 45 min offerings on AF+ that are more challenging?

Thanks in advance!