Since you already know about taxes and trade goods, etc., make sure your Happy buildings are always at a higher tech level than your farming. I usually delay all my farm research until I have several levels of Entertainment already under construction.

Cheers,
Reaver

Yeah. I also find that when I go over 20bil or reach 22bil mark the approval drops like mad. I think the extra tax money is not worth the drop on approval.

I've managed to keep the population happy at the 20 bil mark. At 25, morale begins to drop. At 28 or 29, the morale shoots back up again, though. Did up 'til 1.2 anyway, who knows if they intend to change that.

Anyway, what you need to do is work on keeping your population happy on a planet-by-planet basis. Never fill a planet that's under the 28/29 bil mark unless it's with entertainment. If you do, you'll need to decommission some buildings to replace them with the entertainment. I find myself running into problems usually well after my economy is pretty much stabilized, and so I rush build 2-3 entertainment buildings on each problem planet. I watch as the approval rises (best to keep it at 100 to get through the hurdle quickly), then watch as the pop rises, and when the population gets beyond the definite hump it's perfectly safe to replace the entertainment buildings with economic buildings again. Never try this on a planet under class 16, and never try it on any planet other than a purely economic one.

WRT trade routes, produce more freighters even when you have maxed out your trade routes

What is the benefit of doing this?

Cheers,
Reaver

...it's never worth bosting your pop to 20b on a single planet, go easy on your pop, only build one farm and don't build it one a farm bonus tile and don't research up the farming tech tree.

If you're going for a military conquest or technology victory, this is probably the best thing to do; one advanced farm and one VR center per planet are all you need; bulk up on factories and/or research facilities on the rest of the planet.

However, there are circumstances under which you would want to just max out your population everywhere possible. If you're on a big map and going for an influence victory, or if you want a higher Metaverse score, you want even your average planets busting at the seams with population.

As pointed out above, this isn't really so hot for taxes, since taxes don't increase in direct proportion with population. Also, if you try to max out population everywhere, you will eventually be forced to lower your taxes to 49% or less.

The population modifier for approval caps at negative 80% when you reach 25 billion people on a planet. After that, it's all the same. If a world can handle 25, it can handle anything. I've found that with four VR centers and a low tax rate, I can keep my planets happy enough to keep the population growing and not lose any elections.

I'm still experimenting with this building mode, but I've found that even on a large map, my influence starts to really take off once all of my planets (above class 5) are at 15 billion and a significant number have advanced past 25.

In that game, my highest pop planet is also my economic capital, my political capital, my home planet (the first time I have voluntarily set a different world to be my home planet) and the source of all of my trade routes.

You actually can make a lot of money through trade if you trade between high population planets and build lots of economic star bases with trade improvements along the route. This doesn't fully make up for the low tax rate, but it keeps my income in the green while I'm building planetary improvements and starships on more than fifty planets.

In other words, there is no benefit, its just an insurance policy.

When I am at war, anything in enemy stripes get blasted out of the stars, including freighters, eliminating spies. Good to know the AI thinks differently.

Cheers,
Reaver

If you have some large population planets that are unhappy, so what. Happy people and unhappy people pay the same taxes. And those high pop planets are hard to take over with ground invasions.

All true, but I've had my three biggest manufacturing planets secede because I didn't keep them happy enough during wartime. Since they were also my biggest population planets, I lost a lot of tax revenue, at least one trade route, and, of course, my three biggest manufacturing planets. Conquering them back sapped a few billion people I'd have otherwise used to conquer the real enemies. (And it was just insulting to have my Planetary Defense Centers used against my own men. Ingrates.)

This is a fairly boneheaded turn of events, of course, and it could have been avoided by better management on my part. And that's what I'm trying to learn.

So it looks like I need to build a lot more entertainment than I have. Apparently the one or two facilities I've been using isn't nearly enough for the enormo population planets.

All true, but I've had my three biggest manufacturing planets secede because I didn't keep them happy enough during wartime.

I though secession was due to influence not moral?

Influence from other races causes rebellion, not low morale. Morale effects reproductive rates and can cause you to lose elections if it's too low accross the board. To keep a planet from getting conqured culturally when threatened, build a maxed out influence starbase next to it. You can also build cultural boosters on it that increase its influence points. The little number next to the planet's IP indicates the ratio of external influence. It needs to be less than 4.00

Influence from other races causes rebellion, not low morale.

According to the WWW Link, low morale can indeed cause revolts. I can also verify that the revolt description specifically mentioned their disapproval of my policies instead of the usual "we just don't feel like we belong anymore" text.

If this is a major problem for you take the racial boost to moral at the beginig of the game.