I would have to disagree with the reviewer's comments re: the Civ V overall game.
I have been played every civ game since it launched, even those terrible ones that didn't have sid meir on board.
I find that Civ V
is a different beast, yes it had some terrible bugs on release, and a massive amount of multiplayer issues that until recently had not been solved (some still remain) and tpo be honest it was the same in previous versions. But you have to think far more tactically, go for a cultural victory and you may leave yourself open to attack by a more advanced military et al. You can't just stack 5 billion units on a single tile that is completely defended. Flanking and associated moves are now a bit harder to pull off, but more devestating when you do. Attacking cities is far more difficult and you cannot usually just use one type of unit to do so.
Research is more balanced and a bit harder to run past all the AI players on higher difficulties, no more firing nukes while everyone else is on bows and arrows (although I must admit that was kinda fun)
I find that civ V is the most tactical of the lot, no more just mass producing a stacked army, you have to think about positioning and what is on your flanks when running an army.
You also have to be reasonably careful of what cities you take over/attack with city states and diplomacy.
Overall the diplomacy is pretty haphazard but has been improved a lot, is a lot more consistent now, and lets face it was quite simplistic and broken in the previous versions of civ until the 2nd major update/expansion came out.
As for simplicity? well you can still micro manage every city to the same degree you could originally, it just doesn't put that option right in front of you (off to the side

, I find this to be the case with most of the options I initially thought were missing from the game.
As for linear play style, well civ has never pushed you into a particular play style, some have been much easier than others both now and in the past. the previous civ games were quite easy to win when you went with a domination victory, now it is a lot harder and you have to balance your forces more, I have seen more scientific victories or diplomatic (UN) victories than any other in the new version of civ, the tech tree is reasonable and seems to function the same (although a bit smaller) than previous versions.
I play with a few mates who all have very different play styles, I usually go for cultural victory but I have found my style suits a UN victory much easier. I have a friend who is always a scientific victory and another who goes for total domination, yet another is usually cultural. But switching play styles isn't very hard and often happens mid game.
Now onto the addon:It's basically a new version of culture, boosts that can feed you goodies and weaken your enemies, spies are ok, but I would have enjoyed more flexibility & choice with what they can do, like being able to sabotage buildings etc.
I have tried the Austrians and benefited from using particular social and religious tactics, just marrying into city states is kind of awesome as you can keep your expansion up in the beginning against the comp when playing on immortal.
You can also seriously screw up human players who rely on certain benefits from city states to gain momentum. It does change the way you expand your empire or even block an enemy from gaining a UN victory (marry all his city states

so it does have an impact on your overall gameplay and strategies in some cases. You can also use it to get a strategic city right near a player you may want to accidentally trip over and attack.
The religion aspect is a little under-developed, but still you'll find yourself swearing when someone has all but destroyed your faith and you cannot develop as fast as they can, early games with first contact will find great prophets and missionaries wandering around causing trouble, they can also end up starting wars as comp civ's (and humans) do not like being converted en-masse.
Overall I find it is a decent expansion for $26 (and yes I bought my copy of vanilla from a cd key site that I had heard of years before civ came out; no, no issues) for $50 well if you like civ V it's pretty good, if you prefer the old civ IV then don't bother until it drops in price.
Just my 2 cents but the review did not seem at all balanced or objective, it seemed more like a whinge about why it didn't change civ V back to civ IV (or implement the espionage and religeon the same way) and very little focus on the added features (although light) that the expansion provides.
Regards,
Slipoch