Is there anything wrong with this religious aim or overall view of religious life? No, but it does reveal a rather limited and perhaps somewhat outworn understanding of what religious life encompasses and what religious life has the potential to be.
On the plus side, "mere" cooperation with God is a form of spiritualized consciousness and it does acknowledge the absolute necessity of the human working together with the Divine (unlike atheism which posits that humans are basically sole operators who are either operating with, operating on, or being on operated on other sole operators in a purely material world in which all of the operations are chalked up as little more than random energy events that lack all sense of fundamental meaning or purpose).
The shortcoming of "mere" cooperation with God is it does not address the full potential of Christian consciousness, and it sidesteps the further development of religious consciousness in which the pinnacle of religious life will be something far greater than "mere" cooperation with God.
Nikolai Berdyaev divided the development of Christian consciousness into three stages (or epochs): one in which the existence of sin is revealed, another in which redemption from sin is made available through the willing acceptance of Christ, and a third in which humans recognize and embrace their potential to become divinized co-creators of reality.
All three stages involve co-operation with God, but the manner of the co-operation differs according to the consciousness that delineates the stage. The first two stages - characterized by the Scriptures, religious laws, doctrines, ceremonies, churchgoing, religious hierarchies, priests - exist and are evident in both the past and the present, mostly through externalized forms. Thus, cooperation with God in the first two stages is mostly about aligning the internal and subjective nature of the individual with the external and "objective" nature of God. Revelation in the first two stages comes from up high and has to be externally received before it can be internalized.
The emergence of the third stage, which Berdyaev refers to as "the epoch of religious creativity", requires a new form of consciousness, one capable of transcending the external formalism of the other two stages. This new form of consciousness will understand that revelation can no longer be expected from up high, but that it must emerge from within man. In this sense, the consciousness of religious co-creativity will not look to God for a revelation, but will understand that God is looking for a revelation within man.
Part of this revelation entails loosening our grip on conventional notions of "mere" cooperation with God as a pinnacle of religious life. Yes, co-operation with God is crucial, but the co-operation must move beyond traditional frameworks of humility and obedience of a "fallen" creature and extend into the unknown and, more significantly, the unknowable - the very essence of freedom and creativity.
Religious creativity is a step beyond mere co-operation via formalism for the simple reason that it transforms the core dynamics of divine-human revelation, interaction, and co-operation. Co-operation will no longer simply be a matter of obeying and following the external forms of the Divine, but will be inspired instead by the internal Divine within man yearning to co-operate via creation with the internal Divine that is God in order to add something qualitatively new to reality, something God could not have qualitatively added to reality on His own.
To sum up, co-creation is a form of cooperation with God, but it is far more than "mere" cooperation with God in that it transcends conventional frameworks of divine-human cooperation. The essence of creativity will not be revealed externally by God, but must instead be revealed internally by man. Once this internal self-revelation occurs, a new form of divine-human co-operation will begin - one that will not only mark the real pinnacle of religious life, but also set the stage for the continued development (and fulfillment) of Christian consciousness.