Which version of Genesis would you like to go with? You do know the bible contains multiple conflicting versions...
I do like how you've taken the Ark story and turn it into a bastardized panspermia myth. The idea that earth was colonized by super beings from outer space sounds awesome! I'll put on the shelf next to my book of native american creation myths.
As for the bible, it's a train wreck. You can take the bible and make ANYTHING out of it. It's theological mess, it's a moral mess, it's self contradictory mess. This is why we've got X denominations of Christians who can't decide on any single part of the bible. For every part that you like, you'll find some other group who has issue with it.
However, our fossil record does not contain any evidence of alien origin. We have an embarrassment of riches when it comes to transitional fossils and genetic evidence and radiometric dating that shows that genetically and chemically we're all related. You have lots of DNA in common with an oak tree, and a bunny, and a fish, and a chimpanzee, etc. I'll grant you that maybe some comet crashed to earth 4.5 billion years ago that had a strand of DNA in it and whole process got kicked off. However, until we start catching comets and examining them for evidence of genetic materials or the precursors therein, it's just a hypothesis without any evidence.
Making the argument that the Earth as been geo-engineered for humans is preposterous. 2/3's of it is covered with water we can't drink! Large swaths are covered with desserts and mountain ranges. There are earthquakes and volcanoes, etc.