Hmmm....reading through Flight of the Eisenstein and the Lexicanum/BBB, and a few things have come up that are not quote worthy but still worth mentioning:
-The Terminus Est is a unique non STC design
-It was impossible to replicate because its energy systems were too advanced (Apocalypse, anyone?)
-Still looking for the best possible page to quote, but there is several references to it having a larger lance array than any ship ever constructed by the imperium, which along with it's launch bays made it the ultimate planetary invasion vessel: it was capable of both massive precision lance strikes and had incomparable launch bay capacity.
But I also found a reference to half of its lance arrays being slow and ponderous, with largely fixed arcs which made it difficult to track smaller (read: the Eisenstein) vessels rapidly.
The Terminus needs to keep a strong lance presence, for uniqueness and fluff purposes. What if the prow mount was made fixed, as in forward facing only? Along with the slightly stronger batteries it now has reduced broadside power but a strong forward firepower, which certainly qualifies as special given its parent fleet (chaos). Along with a slight point jump for its now functioning turrets it should work just fine like that, and if necessary making both the prow and dorsal lances str 3 would not hurt too much, especially if prow cluttering is an issue. Although to be fair, there are several pictures of planetary assault vessels facing their prow towards the target planet, so it seems reasonable to assume the Terminus Est has a fairly radical prow design not fully expressed by the model itself.
