I agree completely with the other posters--this super robot is long overdue. As for the question about why Hasbro and Takara haven't released such a robot, I suspect it might have to do with cost and 'interest.' Years ago (during the Beast Wars days) I found a poll on Hasbro's website asking that if they released some Dinobots, would I (or even you) buy them. I responded to that poll with "yes."
Sadly, they delivered on that promise and released Dinobots that had Beast Wars style transforms and weaponry and there was no giant combined form. I guess after that Hasbro figured the interest wasn't there and dropped any further attempts. Perhaps with enough encouragement from G1 collectors they might rethink that decision. After all, didn't Peter Cullen get Optimus' role due to fan pressure?
Finally, are there plans to release a Targetmaster version (no Wheelie) that has an ankylosaurus as the hip and thigh region and the back armor as the chestpiece (much like Snap Trap's shell for Piranacon) as well as a raptor (say, an Ultraraptor) for the gun/shoulder cannon? That I would truly love. It was something I had envisioned since early '86 but lacked the ability to design/build myself.
Again, I think the touches you made to this robot are astounding. I especially love the robot's head as well as the wing-like pieces that stick out from the forearms; they almost look like they have a bladed edge. And, as for the gold paint, it gives the robot a "battle damaged" or "veteran combatant" look to it. It's impressive....