What i like to do is, first charge out with colony ships, send them to as many planets and quarters as you can at first, and once you have 10-20 planets (obviously this is not for small galaxies) then you should have developed your capital enough to get constructors easily.
while your charging, use your flagship to explore the space that's NOT around planets (your colony ships can do that) so that you find galactic resources, and grab any anomalies out there. then once your done colonizing, you know where the stuff is so you can get constructors out there. if you wait to long, the computer gets the resources, if you don't wait long enough, the computer gets the planets, ya gotta find your own balance.
For developing planets, you can have specialized planets for the capitals (political, technological, manufacturing, econonic) and you might have one with alota Galactic wonders or stuff. When it comes to wonders, i generally have alota money on big galaxies so i buy them, and on smaller ones if i don't have enough money, i build, or maybe just ignore. But on all my planets i like to have at least 1 farm, and 2 thing to raise moral, a stock market if possible. is also good. You will want at least one manufacturing building so it doesn't take forever to make all the stuff. once your all fully upgraded in a colony, you can always replace it with something else, or you might have a starport and keep it to make ships. The reason you want a farm is: more people, harder to invade, and moral goes without saying. Also, if you have alota planets with alot a population, your gonna get alota money. do the math, on a small world, 5-7 spaces, your not gonna get that much production or influence outa it unless you specialize, so i generally turn them into cash planets. they won't need much maintanence because there isn't really anything to use it on other, no factories or stuff. so that planet makes money, and if you have enough of these, you can support the heavily specialized planets that lose alota money.
When it comes to research, first i try to buff up my econony, going on to manufacturing, getting maybe 1 or 2 research upgrades (if your gonna go neutral ethics, then your gonna want to do it soon as possible to get those Neutral Learning Centers as Like ro2778 suggested, they provide 22 research, which is better then the 16 from inventing spheres so unless your gonna get a technological victory you don't need to worry about that path any more). After i get manufacturing up, i take a look at the galaxy and see, who likes me and who doesn't. If alta people like me, i try to up my diplomacy skills, so i can trade and eventually make alliances with the stronger of the people who like me. (also a word of advice about alliance research, don't EVER give it away except to people your already allies with. people will pay alot for it but there's a reason for that. once people start allying then one little skirmish can bring Galactic War I down on your head. EXAMPLE: i'm playin a Huge galaxy, i give away alliances to 4 people, they interally. i'm allied with only 1 person, the drengin. 1 of those 4 goes to war with me, now i got 4 enemies and 1 ally (who isn't very big). they don't want peace, so i'm not looking good. and to make matters worse, i'm at the center of the galaxy so i'm also surrounded. I'm dead, but that's gettin a bit of topic). Anyway, Habitat improvement, and the other 2 techs in that branch are nice for those smaller planets because then you can get another farm and moral to support it, which means more money. Getting the entertainment branch up helps so that if you upgrade your farms you don't need a bunch happyness buildings.
When it comes to bonus's that you want to get, it has been said before, and will be said again, it depends on how you want to win. I generally like to have at least one or 2 points into better population growth. With the rush strategy of takin alota planets, many of them will lose money until they get their population higher and pay more taxes, so the faster they breed, the more people there are at tax time.
Starbases: I love these things, they can be the deciding factor in many games. With me, after i've gotten as many galactic resources as i can and upgraded them fullly, i tend to build the econony and production bonusing starbases around my major shipbuilding planets and give them the production boost. Military starbases are good, but i don't use them much except around my very good worlds (15+, +12 in smaller galaxies) and my capital, but other then that, not really.
Well, that's what i tend to do, but you can make up your own mind. after all, that's what the whole game's about, you decide what to.
