Yeah I think Shogi got his wires crossed, the 10x KHH is red (SSJ energy colour is Gold, but SSJ4 energy colour is red) and is done when in SSJ4 form (The form gives you 10x the strength, so the Kamehameha is 10x stronger) Anyway it's GT so it won't get in, though there are sprites for it on ESF-World.
And you say Gohan got screwed over? He destroyed Cell which nobody else could do, won the Cell Games, was the first to ascend to SSJ2, saved the world AND got Mystic as a unique form. If anyone got screwed over it was Krillin...
I wouldn't mind seeing Super Kamehameha as Gohan's KHH's secondary fire, but it's been suggested so many times that they've put it in the sticky for things not to suggest.
As for 1 handed KHH, it would only be logical if it was a Father-Son KHH, which has also been suggested several times, but it would look very odd if Gohan suddenly lost the use of his left arm every time he used it, especially before and after melee.