To clear up the Influence and unlocking paid content question.
It IS possible to pay a large amount of influence resources to unlock or buy paid content such as elite units or additional quests.
Both sides in the above argument are right:
-some elite units you would need to unlock for Influence or $, and then train them in your homeland - for example lets say dwarfish rifleman.
-other elite units, and quest packs, you can`t build but can buy for Influence (or $) - lets say you can buy 3 royal dragon, or a quest pack.
However, since research, and many other things in-game activities consume Influence - it would take a lot of hours to have extra influence to spend on paid content.
And after all - if you spend around 8$ on buying extra resources, quests and units - you will greatly support the developer - since we`ll be getting all the $. In fact when you spend just over 8$ - it`s like we sold extra copy of the game (once you count all the deductions for publishers, manufacturing e.t.c)