Den-O - Imagin based on fairy tales and stories
 

Den-O's imagin surely are related to fairy tales and stories aren't they.

Momotaros - Story: Momotaro - Peach Boy
Urataro - Story: Urataro - Turtle Boy
Kintaros - Story: Kintaro - Golden Boy
Ryutaros - Story: Dragon Boy
Sieg - Story: Swan Lake

Wolf Imagin - Little Red Riding Hood
Anthopper Imagin - The Ant and the Grasshopper
Pig Imagin - Three Little Pigs
Chameleon Imagin - The Frog Prince (which doesn't make any sense)
Ivy Imagin - Jack & the Beanstalk

If only they had more. Some good and some evil.

Camel Imagin - How the Camel Got his Hump
Elephant Imagin - The Elephant's Child
Tiger Imagin - The Brahman, the Tiger & the Jackal

And Den-O would've had a female rider to team up with and she would have her own Imagin.

Only the main characters are attributed to any sort of specific fariy tale or myth. The Den Liner gang are specifically based on the folk tales you mentioned as we detailed through out our Let's Watch Wednesdays segment with Den-O. The staff drew direct inspiration for the characters from those tales. The others however, the Imagin of each week, are based on myths and legends within their contract hosts memories. While not specifically based on particular tales or myths the connections you've made aren't entirely wrong either.

And don't forget the name Imagin is (according to the writers) partly inspired by the Arabic "djinn"- the creature that most of the world knows as "Genie."