I don't think Kant's approach to religion is any longer viable in its original form. But that does not mean it is simply wrong or that we cannot learn from it.

Fichte would identify all states of our minds with states of our body - perhaps not merely of our brain, but the whole body as an acting organism.

Kant can provide, and has provided, a good model for philosophers to think about the relation of metaphysics to science and scientific methodology.

That Hegel's theory is derivative from Fichte's does not prevent it from being strikingly original and of independent value.

Being aware of truths about what is good or right or about what we ought to do is not the same as deciding what to do. Nor can the former truths be derived from decisions about what to do, or about procedures for making such decisions, unless these procedures themselves rest in some way on the apprehension of truths about what we ought to do.

Kant does not think that the silly commandment "universalize your maxims" is the be-all and end-all of ethics or that it provides us with some sort of general decision procedure that is supposed to tell us what to do under all circumstances.

Kant thinks of judgment as a special faculty or talent of the mind, not reducible to discursive reasoning but cultivated through experience and practice.