Some 30k podcasters spoke to the Forge World head honcho at the recent Open Day. He said that they haven't started working on BFG yet, but personally, he'd really like to see a boxed set based on the Siege of Terra, with xenos expansions coming later (in a different setting, just as Armada was not about the Gothic War). They're trying to release one Specialist Game per year: Blood Bowl last year, Necromunda this November, Adeptus Titanicus next year, and that's as far as they've gotten.
The 30k setting hasn't resolved ship aesthetic issues at all. You've got Gloriana-"class" battleships depicted as looking very different from each other, like the Macragge's Honour looking exactly like an Emperor-class ship in that 2014 comic, but the Iron Blood looking like a larger, modified BFG Battle Barge in the third FW Horus Heresy black book from the same year. In the card game ten years earlier, a couple were depicted as Emperor-class (-ish) battleships with plenty of artistic license, but the World Eaters' flagship had a Chaos-styled rear upper hull like the Vengeance-class. I'm not sure it should be considered a class in the conventional sense.
All the escort class names in the 30k novels are familiar, but I've seen the Gladius-class Eisenstein depicted as a Sword-class in official art (probably from that card game, which came before the Black Library novels).
