Rational? No. Moral? In the absence of an absolute, transcendent moral authority, "morality" becomes impossible. The idea that something as collective (and absolute) as right and wrong can somehow be individualized is a contradiction in terms.
And there is no rational reason NOT to believe in God either. In fact, it is just as logical to believe in intelligent design as it is in cosmic evolution or random chance.
Finally, belief in God, and more importantly, His principles, is not a matter of reason, but a matter of Faith, "the belief in things not seen."
Had God not ahown up in person to tell us who He was, it would be illogical to believe that there was a God. That's, because the belief would be in something that no one could see, or examine on a consistent and rational basis.
As I said in post 21, the person that did present Himself as God did show up, and he said no physical evidence whatsoever would be given. That includes evidence of design. He gave his reason, and that was so only His Spirit was to be the evidence on examines to know Him and believe in Him. One's judgement of that Spirit and honest incorporation of that Spirit as one's own is the sole basis of salvation. Salvation being the continuaiton of life with God and others of like spirit. That was given in Matt 12:32
"Anyone who speaks a word against the Son of Man will be forgiven, but anyone who speaks against the Holy Spirit will not be forgiven, either in this age or in the age to come."
"belief in God, and more importantly, His principles, is not a matter of reason, but a matter of Faith, "the belief in things not seen."
It's not rational to believe in what can't be seen, or examined. That's not the case with God, since He came and taught who He was and what He was about. As He pointed out, it's the spirit that's importent, the physical machinery that supports that spirit in this world. Examination and judgement of God's Spirit, or any decisions regarding one's own spirit, requires a rational examination and judgement. As I pointed out, that is required and it is the basis of salvation.
Examining the physics of this world to search for God was never to be allowed. From the beginning access to the tree of life was forbidden and a cherubim wielding a flamming sword was assigned to guard it. That cherubim is the physics of this world. The beauty, knowledge and understanding of God is to be found in His Spirit, not in the physical machinery.