0% tax rate does not yield 100% morale

In galciv1 your peoples morale was slower than it wil be in GC2 in GC2 thats because of crowding,lack of Planetary improvements Imperial debt stuff like that can have a determinable effect on ur aproval rating but don't try to strive for 100% morale until ur economy is superb and can risk lowering taxes really and in The beta you can't trade ANYWAYS so tis kinda retarted to reduce taxes as tis ur only source of income... in most city buliders if you bulit high-class homes and taxed them their tax money will be higher than what it costs to pay wages and can cover some imports.

I think morale is now lowered by the number of people on the planet compared to the number of farms on the planet. If you have more people than your farms can sustain, you suffer morale loss.

This is only from experimentation, not from the word of the devs, so don't take it as truth just yet

Below are the factors of my observations:

Cheat enabled: Planet has a class of (30+) in which all tiles are available. I explain how to do this in another post.
Researched all technology
All available improvements are available (though I'm sure there will be more)

Ok, now at 1st I just started loading up on farms. I had over 20 of them with all of them as ultra advanced farms (or whatever they are called). I have an insanse population growth rate which actually could caused problems if you can not keep your morale up. I had plenty of farms but not enough entertainment for the masses. My morale quickly dropped as the ratio population vs entertainment increased. I havent actually tested to see what happens if your morale drops to 0%. However, I have discovered to keep your morale up you can lower taxes or build culture type facilities to improve your morale. In the this test case I use entertainment. Now I had to pack them in. Because of the population density that ultra farms can sustain you have to allocate alot more space for entertainment facilities to maintain your morale as your population increases. I'm going to take a guess and say that there will better entertainment facilites later (beta 4) because the ones available do not pack much of a punch. I have well over 30 entertainment tiles to keep less than 10 ultra farms at about 70% morale with a 20% tax base.

Money: Well I have about 10 tiles for this, mostly banks. Dropping the tax rate has some impact but not as much as placing entertainment. Although my vision could be a bit skewed because of the cheat i'm using. Most likely we will never get a planet with all the tiles available. Note of course with a larger population you have a larger tax base so you can bring down your tax rate somewhat due to this factor as your population incrases.

Also one more item:

I've noticed that population fluxs once your farms hit peek production, thus so will your morale. At one point in time I had 5 billion people die once we hit the max then the population would climb and in about 5 turns we would have a mass die off again. Keep in mind 5 billion was a small percentage of my total population.

Why should 5 bil be breeding and then starving? Aren't their population controls?

Once population hits the food production cap it doesn't grow. People don't starve in the game by default.