Here are my current thoughts on Balance for Policies (I will add more as I remember them). For ease since there are a large number of these, I am going to give them a quick rating:

A - Perfect Balance. I think this is a great policy that just does its job well.

C - Decent Balance (either a bit UP or OP). This one is either just not quite carrying its weight, or actually a bit too strong and I find it hard to leave it.

F - Bad balance. These policies are either so crazy OP I have to have them, or so weak I never use them.

* - This policy is very "gamey" (see my general note below). Most of these are OP because of this nature, and I have rated them as such. If it wasn't so easy to swap them, I would rate them lower.

General Note: In general, I really like the policy concept...with one exception. There needs to be some kind of cooldown time when setting your policies, as its far too easy to "game the system" right now with them, where you set a policy, do a few actions, change it, do some other actions, etc. 

Specific Policy Notes

• Ban Dissent (F) - If this came earlier in the game, it might have some relevance, but by the time I get it, I've moved on to the bigger better econ bonuses.
• Bureaucracy - (F*). Completely OP in the proper hands, as you can just create large fleets with it, then swap it out, suffering no penalty. A smart player can increase their military strength markedly with this policy, with no drawback or downside.
• Coerced Colonization (A) - A good starting policy, that tends to draw down naturally as the game progresses. It does its job well.
• Conscription (A) - Probably one of the best balanced economic policies.
• Cultural Values (C) - The penalty is not too bad, but I also find that when I want to push influence, my bonuses are so high that a simple +10% on top doesn't move the needle, and if I'm not going big influence I never want this. So it has its uses, but its not all that strong.
• Defensive Measures (F*) - Number 1 war policy in the game. Its incredibly gamey, and frankly has no down side (because I have not once had the range penalty really affect me in a way I couldn't mitigate with a starbase).
• Eugenics (F) - Its a cool policy, but its just too random to be taken seriously in the face of overt strong bonuses. I really want to take it, but I can never justify it.
• Experimental Drives (A*) - While you can game this, I find its not nearly as bad as other gamey policies, its just a solid bonus very strong in the early game, but has trouble competing with economic policies and so tends to balance itself.
• Free Media (A) - Its only useful if your going a strong diplomacy build, but if you want that this is the policy for you, and it does its job well.
• Free Trade (A) - Ultimately if your going heavy trade the small increase in crime isn't going to hurt much, and the boost can be quite significant if your focusing on this strategy.
• Genetic Manipulation (A/C) - You have to work to make this policy cool, mainly by having a LOT of scientists (Iconians as an example), or you have a lot of leaders in a faction that utilizes INT...but I really like this policy, its fun to work with. I think its normally a C, but can be an A if you have the right build for it.
• Genius Grants (A) - Strongest research booster by a good margin, but still seems decently balanced.
• Heart of the Empire (C) - Generally I only use it in the early game when no other policies are really hitting the bill at the moment, but its not a great bonus. Frankly even if it effected all of your planets it wouldn't be amazing.
• Infrastructure Support (C) - A fine bonus, but not affected the homeworld (which is often your best manu planets in many games), is a big hit, as is the income penalty. It has its uses, but its just alright.
• Land Exploitation (A) - This is a good balance of power and tradeoff. The income bonus is very strong, but that pollution hurts, and so its definately a balancing act of when to use it.
• Military Stimulus (C) - I think its a little bit OP, I use it the vast majority of the game, as its such a strong bonus that is always useful all the time, and you get it fairly early in the game.
• Open Immigration (A): A nice solid well rounded eco policy, provides a number of benefits with no drawbacks, but none of the bonuses are so powerful as to be OP. Just great, I really like this one.
• Planetary Stimulus (C/A) - I go back and forth on this one. On the one hand, I consider it the best eco policy in the game, its basically always on for me once I have it, unless I'm in total war mode. On the other, it does take a bit of teching to get it, so its a nice benefit for an area of the tech tree that isn't all that strong to begin with. So a tough call.
• Police State (C) - I use it on occasion if crime is really a problem, but control is not a strong enough resource to generally justify this.
• Protect the Planet (F) - The main reasons to lower pollution is to increase growth (which you can do better with other policies), and to gain food (which I would rather just make a few farmers and call it a day). Penalizing my manu hurts!
• Prototype Defenses (A*) - Very gamey right now, but honestly the bonus is not actually that strong, once I understood how weapon attacks were normalized. It doesn't come into play as much as you might think at first glance, and so I think its just a solid war policy.
• Rationing (F) - The issue here is, starvation gives you penalties to growth and approval....which this policy also does. Yes the savings in food can be significant, but I just never find a need for this guy, as the savings have to be pretty large to just accept a big penalty to the two things your trying to avoid penalties in.
• Reduced Regulations (A) - If your playing big money, this is a pretty solid bonus, and the penalty is not that bad. NOTE: There is a text bug here, the policy says it only works on the homeworld....this is incorrect, it does (and absolutely should) work on your other planets.
• Research Grants (A) - Its a fine policy when you get it early, and though its 100% inferior to Genius Grants, its a fine policy to combine with G grants if you want to go "hard research".
• Security Lights (F) - Terribly weak policy, even with high crime I just can't rationalize this versus other eco boosters. This is probably the number 1 weakest policy in the game.
• Starship Specifications (C*) - Its a really good war policy, and very gamey (so a bit OP), but at least does have a penalty worth talking about. 
• Wealth Tax (A) - Its a great one combined with Land Exploit to give a really big eco booster, for the hard money play.
• Unregulated Research (A) - A fine add on to other policies if your going "pure research", as it has no penalties. I would never use it otherwise, but its a solid enough niche.
• Universal Health Care (F) - I find by the time I get this policy its hard to care about growth, and often another 25% doesn't move the needle much when your population is already large. You can combine it with others if you want to go "raw growth", but growth in itself is just not strong enough to normally warrant this push. There are simply better things to do with my slots that have stronger and faster payoffs.