You need to be more flexible with your character. I was easily able to modify my character's backstory when I found out how much people are annoyed by some of it.
The original story of Draykon:
After being defeated by Fox McCloud, General Scales returned to his project of mutating the Saurian population into Draconic beasts. The most powerfull one he created was a beast called Draykon. This beast went rouge and began to use it's power of absorbtion to gain massive power as it jumped dimensions.
What's wrong with it:
For starters, I've tied the story into that of General Scales somewhat, this is bad. I've also identified Draykon as being rather overpowered, which is also bad.
The slightly-better story of Draykon:
Every few years a creature called The Master will call the universe's greatest fighters together, in what is known as the Super Smash Brothers tournament. This is actually an effort to gather DNA from the all these fighters and create the ultimate warriors. One of these creatures is Draykon, a powerfull Meta-Human with the power to become a Dragon, and the ability to use nearly any attack ever used. Draykon went rouge, and now seeks to destroy the Master.
What's wrong with it: This is a bit better, but I've still tied the story into that of SSB. Also, though he's toned down somewhat, Draykon is still rather overpowered.
The current story of Draykon:
Dr. Ivan Embrake was ridiculed by his theory of the Ultimate force in the Universe, known as the "Omni" His collegues were shocked when he actually did create this power. And became a powerfull being known as The Master. The Master then created an army of draconic beasts, as well as a very short series of Bioweapons, the Vokelda project. When he found the projects defective, he attacked them. They (Who included Draykon) managed a narrow escape, and now seek to destroy the Master.
Why this is good: Although I didn't write about it here, I toned down Draykon by alot. Also, if I were to publish this, I could legally copyright everything except The Master's name.
Right now your backstories are alot like the second one. Make them like the third one and they won't be ridiculed so much.