So you believe, on faith, that there must have been a simpler one-celled organism than exists today? You have no proof in any form. I don't believe things on faith.
No one said anything about faith. We have 3.6-3.8 billion year old fossil microbes. They existed - no faith. The fact that they no longer exist does not make them less real, just as the fact that Tyrannosaurus no longer exists makes it any less real. I also understand evolutionary processes and a 3.5 billion year old bug wouldn't stand a chance in today's more highly evolved and more highly competitive environments. Not to mention that the environments of today are much changed from those of 3.5 billion years ago.
Since we don't know the details of a 3.5 billion year old bug, your point as to the complexity of single celled bugs is meaningless. You may be right, but IMHO you are most likely wrong.