Yeah likely the Gotha. The originals from 1974 were more based on the American Flying Wing that was much more well known at the time.
I will say that the episode 3 preview with Kirishima
together is quite a nice touch. In the original, after the old Earth Flagship lands at the middle of the first episode we never see it in space again (aside from the usual flashback to the Battle of Pluto). There is also a lot not in that preview. They show the ship starting to Warp from Mars to Jupiter, but not much else around that event...and I'm positive there is some interesting stuff going on come episode 3.
But that, episodes 4, 5, and 6 will be released together June 30th in the theaters. Then the BD come out July 27th...were most of us may be able to see them.
From the translators notes it seems these ships now have shields. Or at least some form of barrier that protects the hull for a short time before anything even gets to the armor. Also the notes say the Cosmo Zero, as a squadron leader fighter, has a barrier system to help defend the rest of its squadron mates.
Notes place Yamato's fighter strength at 2 Cosmo Zeros and 36 Comso Falcons (the new name for the Black Tigers...because today in Japan, "Black Tiger" is a type of shrimp, and the "Falcon" was the Imperial Army's fighter compared to the Imperial Navy's "Zero"), plus a small number of other craft.
Yamato has more or less the same weapons she had before, though they have added a set of missile launchers on her underside (a long unprotected side of the ship). That and she is a little bigger than before at 333 meters long (which was reportedly what she was scaled to in 1974, but reconned to be 265 meters to match the IJN Battleship Yamato's length in the 1977 film version of the story). Also means her guns are bigger...the main guns are 48 cm (roughly 19 inch guns) while the secondaries are 20 cm (8 inch guns). The Wave Motion Gun is 200 cm wide...though it looks more than two meters wide to me. Maybe that's just the round part in the middle and not the opening in the hull.