Here's how and why it all happened if that helps you....
After Lord Buddha the teaching was kept alive by the monks who learned and kept it by heart, they did it in few different ways. Some individuals kept it all while some learned chapters.
Time to time they would come together for a reciting. This would be called a Council, It is essentially a global gathering of monks who have the teaching by heart. Here they would each recite the teaching that they have kept. This was done to clear any doubts and clean the error as all the other are listening and chanting too.
In Sri Lanka the same tradition went on until an all island drought came. Some monks went to india and some stayed in the island. They hardly saved themselves but a lot of Arahats passed away because of the drought. They decided that the Oral tradition is not reassuring as they saw it first hand. So they did another Gathering or a "Council" and this time they wrote teaching. This Became the "Tipitaka" of Theravada.
So the whole process was done right and transparently.
This is how it happened. I should remind you that if one chooses to put away the tipitaka he or she ends up with nothing else but his or her own version of things that his or her mind construct to benefit. Without the tipitaka there is no Buddhism left to follow.
I must say that one thing you said is wrong. It is not a Buddhist thing to make our own version. I agree that we all interpret the teaching in our own way, but one should not make personal beliefs. But the teaching is open to different interpretations as we all are with different wisdom and intelligence.
Namo Buddhaya!