Personally I believe in being the strongest before declaring a war. Use diplomacy to stay neutral until you have things set up to win. You need more planets than the AI, better manufacturing and research. Focus on building your empire for at least 50 turns and then start researching better weapons and bigger ships. If you are diplomatic you can trade for low level weapons early since the AI get them first.

Nah. On Godlike mode, you are going to be trailing behind by leaps and bounds for the first 150 turns or so...at least.

You do not really need more planets than the AI either. You probably will never be able to outdo them in colonizing with the starting resources anyway (unless the map resources just happens to favor you).  it is better to have tight clusters of planets so you can pool their resources into a single shipyard and build less star bases to boost their production. Well, it just depends on the generated map. If there is enough space between your planets and the AI, they may never send a transport your way even after they have laid waste to everything you have in space.

As for research, you will never be able to outdo the AI either until mid to late game, but you should be stable by then anyway. I find that you do not have to put extra effort into research. It is more like researching the right tech at the right time will be more beneficial, but even this is not a must. Just go as you always have and you will be fine.

Your best bet in surviving and winning a Godlike game is to play the right Ideology relative to your neighbors.

Yes, who your neighbors are makes a big difference. For example, if you play benevolent, you would want the Iconians and the Altarians as your neighbors. They will never declare war on you as long as you yield to them for a while. Other races with opposing ideologies like the Yor would still declare war on you, but it is less likely since you may be out of their travel range or take a while to reach. They may also declare war on your neighboring factions with the same ideology, so you have a bit of a shield buying you time. it is also good to research some diplomacy, particularly Exploration treaty so you can sell for credits and get a good view of potential enemies coming your way. That way, you can build your ships accordingly to counter your enemies before they reach your ZOC. Of course, this implies that starting out in the middle of the galaxy is one of the worst places you can start in. 

Over all, ideology will determine your fate...literally.

Thanks!

Makes me more happy when i can win on a random map/size with one strategy.., but the cruiser strategy is impossible to get for all maps