“The imperfection of biology suggests ...”
Spotting “imperfections” would require an understanding of Creation that no man can posess.
“A supernatural being/God doesn’t have to create through complexity.”
“Complexity” is a reletive term. Anyone who can understand all of Creation may not regard it as bing all that complex.
Imperfections are called "disease". It is spotted all of the time. At the time of Jesus, everyone thought that infectious disease was caused by angering God. Now we know it is caused by microbes. Penicillin has cured more people than all of the saints combined (except Archie Manning).