Obviously, as those who follow the EU closely know, the Empire does have ships in the size-range (more or less) of the Tantive IV, so FFG *could* have used those...
But, why would they? It would require interest in the EU - a level of acceptance of the EU that (notably), many on these forums just don't have. The Tantive IV and Rebel Transport, in contrast, are selling to not just X-Wing players, but fans of the Star Wars 'canon' universe in general.
So, yes, FFG *could* release an EU-only 'huge ship'...but they'd be cutting their audience in half.
So why do that? Why not wait just a couple months for a pile of new Imperial ships in this scale to appear IN CANON.
Recall the new series coming up...
...note, particularly...
1:36 - Imperial Gozanti cruiser under attack
1:44- Imperial Gozanti dropping off some AT-PTs
1:46- Imperial Gozanti launching TIE Fighters
Just one example, but the series is introducing SEVERAL new Imperial ships in this scale...and none are "EU". This is 'film canon', here. The exact type of thing you can release a product for that gamers will buy and fans of the film and TV series, but nothing else will also buy.
So...yeah, it would only make sense for them to wait until this is actually being watched by everyone. Indeed, it's entirely possible Disney *required* FFG to wait on releasing these designs.




