So I was thinking about the size of the models and contemplating how big we'll see Armada get. I'm kind of doubtful we'll see Super Star Destroyers or similar sized Dreadnoughts. The Victory class is like 900m and the model appears to be approx 2 inches+. The Executor, Vader's Flagship in ESB and RotJ, was over 20x larger than a Vic. That puts us at nearly 4 feet. Even if the stick to the Cinemagraphic play/scaling format, going any smaller than 2 ft really just does it disservice in scale, but I could see them doing that. Imperial-Class Star Destroyers are not quite twice the size of Vics, so lets call them 3.75" long, while Rebel Mon Cals are going to be around the 3" range, being about half again as long as a Vic.
Victory Class are 900m
Mon Cal Cruisers are 1200-1300m
Imperial Class are 1600m
Executor is 19,000m
Death Star is 160,000m
Death Star II is 900,000m
Edit: The Corvette appears to be closer to the 2" range and is 150m. Neb B is 300m, so should be twice as long, but they are not. They are almost the same size, model wise. The Vic appears to be about twice the size of the Neb B model, though it should be 3 times the size of the model if everything was scaled the same.
Which brings me back to the above, I imagine we'll get the Executor as a "Giant Ship" like the Corvette and Raider in X-Wing. Probably about the same size as the 3 X-Wing ships, too, I'd imagine. It will still dwarf the other ships.