Ahriman
Tyrant
I'm not sure what criticisms are involved here. Oligarchy seems like the only real weak link here (I find it fine but I play wider usually than most I'm sure) and even that will be okay when the AI is aggressive early on again. "Legalism" could be improved by moving the culture borders effect there from the opener. Aristrocracy just needs a light bump in production on wonders and rid of the gimmicky happiness benefit. Landed Elite could get one of the growth effects from the finisher and then we could move on to other trees.
Maybe give the opener the +1 on later culture buildings effect (something that wouldn't add much early but would be useful down the road). Instant yields might be interesting as well, possibly on monarchy.
This basically sounds fine, but the one outstanding complaint I'd have is about legalism. It's really annoying that legalism is a pre-req for other policies. Free buildings should be something you can time somewhat so as to be able to get more expensive buildings; as it is, you're always just going to end up getting some free monuments, which is pretty boring and lame. Faster early game culture isn't really something you need, it doesn't have any particular Tall synergy. I'd prefer to drop this effect and add something else.
So how about:
Opener: +3 culture in capital, enables hanging gardens, +1 culture on ampitheater, opera house, museum.
Aristocracy: +15% wonder production, +1 culture per world wonder.
Landed elite: +2 food in the capital, free aqueduct in first 4 cities (when tech is available)
Monarchy: +1 gold and -1 unhappy for every 2 citizens in the capital.
Legalism: Faster border expansion and ???
Oligarchy: free maintenance for garrisoned units and and +50% ranged strength in cities with garrisons.
Finisher: +15% surplus food in all cities. Great engineers purchased with Faith in industrial era.