As Ruckddog says. The AdMech cruiser follows the rule for example from an Imperial Lunar Class with the added special rules from the pdf (eg dorsal lance, gift of the omnissiah).
Same to the light cruiser.
Different model as Imperial Navy with same basic stats. But added flavour.
The battleship model can also be build as an emperor, Retribution or Oberon.
Here's an updated version of the rules:
http://tinyurl.com/23nul8q
I have an 1500pts AdMech fleet. First battles I lost, then I started winning. Equal now. So seems balanced.