Some answers to your question:
FTG is made for all players who want to act more as the Government of a country than an almighty god. Player takes important decisions (alliances and diplomatic relations, warfare, investments, exploration and colonization…) but he also has to deal with decisions and personality of the monarchs through centuries and adapt for the best of the country. Nothing is written in stone and a wise Government will play with History and take advantage of it or do what is to be done in order to change it.
Our goals is to provide historical situation but a player can change everything while playing. In this case, historical events out of context will simply never occur. Script engine has been greatly enhanced in order to provide better control of the situation in triggers.
All play styles are possible from role-playing countries to World conquest. The game proposes an historical trend but this far from rigid and many plausible alternatives are proposed in AGCEEP like England winning the Hundred Years War, China still open to the rest of the World and more exploration oriented, formation of Germany, etc. Player has a choice and can influence ruler’s decisions... but not always according to situation.
For the same reason, AI controlled countries will try to act historically but they will also adapt to the situation. The game also proposes different levels for AI choices in events from pure historical to fully random.
An excellent answer, but one that, to me at least, does presuppose familiarity with EUII. I realize that, as licensed developers, and not Paradox staff, the limits are greater on what can be revealed and when, as Paradox still owns the property. I do hope that an effort is being made behind the scenes with Paradox to develop a marketing plan to embrace the newcomer when the product is ready for the wider public.