[quote=@Adorabadass]
<snip>
And I see no reason why any of us couldn't learn Kaioken,
[/quote]

I agree with that, but having some customized transformations much later on would give us a chance to shine a little. Plus if we go by some of the logic from the filler episodes there is one point where Goku goes Super Kaioken (Super Saiyan and Kaioken) so any Saiyan would have an instant advantage. But maybe I am focusing in too much on Transformations, they're one of my favourite parts of the DB universe.