My thought has always and will always be this:

The shot opens on Star Destroyers. They are big.

Then the screen is filled with something flying overhead. Is it an entire Star Destroyer? No, its just a huge tower of something bigger.

Another shot of Star Destroyers. They are big.

Then a shadow crosses over one of them. Something bigger.

Trying to replicate the beginning of ANH just focused on a small part of the ship that was in ANH doesn't make much sense to me. It's supposed to be something bigger. The reason the tower doesn't look different is because they had already built it for the Falcon being attached. They colored it blue in the original version so that you would know something is up with this tower.