Also, I noticed there are a different number of ancient personage cards for Kings, Citizens, etc... what happens if - for example - a player destroys a temple but there's no Generals left (I think that's the right card)? I assume it's a case of 'tough luck' & you just have to try & get some of the other remaining cards?
Correct. The rules state:
3. Winning Ancient Personages
At the end of a turn, a nation collects one or more ancient personages if it meets the requirements for each, and the bank still has them available.