Here's my opinion of policies and the picks within that could use some tweaking.
Tradition: A pretty solid tree IMO, not many changes needed for a vertical growth focused empire.
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Aristocracy: Could us a bit of a buff. Say 25% instead of 20%. Early wonders go very quickly from people rushing a GE off a policy.
Liberty: Its a nice tree, but I would personally like to see some tweaks to it yet.
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Collective Rule: +50% settler production in cap. and +1 gold per city.
REMOVE free settler
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Republic: +1 hammer per city. Free Settler moved to here.
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Meritocracy: .75 (or perhaps .66) happiness per trade route. +1 per trade route is too strong when paired with Honor- Military Caste, but a slight buff would be good.
Honor: Solid tree if going on the warpath for an extended portion of the game. Certain leader abilities warrant use of it more than others.
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Warrior Code: An early GG can allow warriors to actually capture cities with fewer casualties. But the window of opportunity here is very small, so this one needs a lasting effect. I'd say either remove maintenance from barracks or free barracks in all cities (or both).
Piety: Probably the best tree in the game with the golden age and happiness benefits. Completing it gets you one free social policy to boot.
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Theocracy: Consider adding a penalty to this one of -10% research in each city since this allows tremendous vertical growth which overshadows the rationalism tree greatly.
Patronage: A decent tree. If trying to hold onto some key city states this can help save a ton of money in bribes. Key for going for the 'diplomatic' victory.
Commerce: Powerful and weak at the same time. About half of the picks here are good, and half are bad depending on your circumstances.
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Naval Tradition: When paired with the great lighthouse and/or England gives you a speedy and responsive navy. However I'd like something a bit more tangible for the cities to use here. Either Free Lighthouse or Harbour in each city, or maintenance removed from Sea based buildings (Lighthouse, Harbor and Seaports = free maintenance).
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Trade Unions: Bump up to 25% reduced road maintenance wouldn't be so bad I don't think, as most of my cities need between 3 to 6 roads to be connected to my trade network. That would be basically 1 gold per city essentially, as it is now, its about .5-.75 gold per city depending how spread out the empire is.
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Protectionism: +1 Happiness per Lux resource AND +1 happiness for each extra luxury resource available to the empire (so if you had 5 dyes you'd get +6 from first, and +4 from the extras). Would not be able to trade other empires for any extra luxury resources you already have. (So if you had 1 cotton from yourself or another civ, you couldn't ask for another cotton from another / the same civ.)
Rationalism: I do find the tree a bit weak, but when paired with liberty or freedom I think this tree can do well as long as you keep your population in check to avoid stagnate growth in key research centers. The problem becomes that typically finishing the Freedom tree is more enticing than opening up this tree mid ren era, and by the time you've reached industrial you have to choose between rationalism and order. If the order tree opened up in the Modern era than this tree would get more use I think, but then Order would be very late in the game to have much of an impact.
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Policy Unlock: Starts a 5 turn golden age and during all golden ages research (AND Culture??) output increased by 50% empire wide.
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Humanism: +1 Happiness from each University, Museum, and Research Center. (threw in the museum instead of public school to spice it up a bit).
Freedom: A solid tree. Could forgo Piety for this one to get some happiness relief right from the start, as well as much quicker policy gain if empire has wonders spread out.
Autocracy: I've only unlocked it once for the achievement and didn't really need it. It needs some serious reworking that I haven't really contemplated too much. I liked the posted idea for total war, and I'd like to expand on it. I think if there were a war weariness mechanic in the game then this tree could get some major benefits to counter it. As it is now it is hard to fix without making it too strong, as war is the most effective way to win the game.
Total War Any Civ that you have denounced will be now be at war with you, and units fight with a 25% combat boost against those civilizations until peace is reached. This effect can only occur once per civilization. (maybe give a 15% bonus when attacking as well. This is at the end of the tree so it needs to be STRONG. As it is 2 policy unlocks in order can nullify most of the effect if the defender is fighting in friendly territory.
Order Decent tree, though late arrival means less impact on the game. The 5 hammers is hard to beat regardless though (over 1/2 of a ironworks per city, yes please! Or if you can get the trifecta of republic, merchant navy, and communism, 10 hammers per coastal city

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