Headcanon 1
Steven and Shoutmon's battle system are the only different ones from all other tamers

Shoutmon has a choice to battle along side his dragon comrades

While Steven's battle system is simular to Attack the Light - Unleash the Light
In a nutshell Steven just fights along with his dragons since he would probably replace the Healing Light skill, Healing Fountain, and Healing Potions

Headcanon 2
Greg used to be a dragon tamer, and Cloud was his dragon...and that means Greg handed down Cloud to Steven-
The reason Greg stopl doing dragom taming stuff was because of falling in love with Rose Quartz
So Cloud stayed around hatchling level before Steven started doing the dragom taming stuff
But...at first Cloud uh... "disliked" Steven, he kept his distance from the hybrid
So during Steven's early days going on adventures with the gems (-S1-), Cloud was just a minor character...so he barely appears
But as soon as Steven got attacked by the homeworld gems, even getting kidnapped into space and onwards (-end of S1 - SUF-) Cloud grew a bond with him and evantually they grow insseperable (-is that how you spell it?...-)....and probably the reason why Cloud is very protective over Steven-