Does the Darwinian theory require modification or replacement?

The only thing I can contribute to talk of genetics and evolution is that genetics is not a trail.
Since creationism sees a great blueprint or computer program for biology then it follows that there is simply a dna score for parts and processes in biology.
for example I discovered marsupials are just placentals with some late adaptations. yet evolutionists try to say marsupials are a group from some ancestor and unrelated to placentals. They invoke the dna formations as showing the marsupials have like dna but unlike placentals.
Well then this demonstrates that the dna was simply a atomic manifestation of the biological change from placental to marsupial.
In short all these creatures got the same dna score because they had the same thing happen to them.
Like body change equals like dna change and addition.
So drawing conclusions of biological relationships from genetics is a waste of time except in minor cases of very close and obvious relationship.
Genetics is not evidence for evolution but it has only been a line of reasoning.