Playing an Empire game, I noticed I was unable to build parties. I had a level 3 city and picked up the first party technology. The box never un-greyed for a party of more than 1 unit.
Also (possibly my ignorance), the "Imperial" tech tree was unbelievably short. I finished the tree off except the advanced "Majesty" line, but still had no better buildings than huts. I found that between the lack of housing and the higher pop-cap (500 for Empire where it was 400 for Kingdom) it was unfeasable to get even one city to level 4. Is this intentional? I didn't see anything about it in the manual.