Yep, they're right, the oberon can be made by swapping the forward pair of launch bays on an Emperor for a pair of lances. If you really want the Voss prow, glue some toothpicks or other stuff to the front of an apocalypse with the bays set up the right way. You might want to get a pin vise if you're going to try that, and fill in the torp tubes with green stuff.
All battlecruisers/heavy cruisers are made off the crusier hull, except with dorsal lances added, which is good news for you, because that's the cheapest source of ships in the whole game, and they're the easiest to convert. If you want them to look more important, I'd recommend making engine shields out of plasticard like you see on the battleships or something like that. The only minis I know of they stopped making is the Voss light cruisers (Defiant, Endurance and the other one)
The Machine Cult could be an entire faction by themselves; they have their own line of minis! Which is somewhat irksome, as they're getting new models and I still can't find a bloody Oberon battleship...
Regardless. Another idea is to not have desert, terran, etc planets, but rather have forge worlds (more logistics slots), agri worlds (LOTS of hitpoints), etc. Thta would put a much more '40k' feel into the way the game plays.
All that is on the feature list. I suppose we should actually get that together one of these days...
Also, once my current batch of schoolwork is done, I'll get to work on getting the planets we can do with existing effects done and making more summaries of game mechanics.