Technology and Economy. Period. Especially in a normal game. Military is all fine and dandy, but you can pass by with a small (not weak, but small) military if you have the technological and economic edge. Build Economic Centers (ie, Markets, Stock Markets, etc) and also keep up with the technological edge. Set priorities when it comes to technology: Do you really need to research those farm improvements? (hell no). And make sure your always working at 100% on the slider bar, or as close to it as you can be.

farms are extremely important economic base, one farm does more for your economy than an economic building (if you can keep all those people happy of course) usually for me i set one of my high quality worlds (usually 12 or above) as my economic powerhouse i build 2-3 farms (depending on wheather i have moral reasources or not) 4-5 moral buildings and the rest i just build the economic buildings

one or two planets like this plus building one farm and a moral building on some of my planets that are big enough to handle production centers and an economic boost usually gets me by good in the game

I usually build up my economy and research. doesnt matter wich planet i ALWAYS have 1 farm (i tend to get the bonus tiles on almost every planet) and 1-2 economic buildings. On EVERY planet. I then have research stations for the most part and a couple off economic star bases. I only have production planets if its a 16+ ^^ the more factories the faster they poop out ships

Expansion expansion expansion, it's all about expansion and early in the game. Take Ion drive right off the bat and build you a movement 5 colony ship and BUY them. Don't wait for them to be built by industry. Travel out as far as you can go and try to get those 10pt planets early. Then worry about the miniscule planets behind you later on when your big productive planets are churning out colony ships in a few turns. You also don't have to stock every colony ship with 500 pleebs. I get by on 200 or 100 most often. Just enough to colonize a planet and keep on colonizing.

Once most of the planets are colonized then it's banking time and manufacturing. Technology is ok, but, it's not that necessary to stay ahead of the game as economics are. If you don't have money you can't do much of anything. Don't be afrad to borrow in the early game, but, not too much. If you borrow too much then you ruin your economy early on. This takes practice to find the best borrowing limitations.

Early in the game have one of your planets producing the cheapest fighter class ship you can make. Anything, something with a weapon on it and start defending each planet you have with at least one of these. The AI is too stupid to know you have cheap military ships it only recognizes HOW MANY YOU HAVE for military might (hope they are fixing this in 1.3).

Trade Trade Trade. Each turn check the STATS tabs of your opponents. Down at the bottom shows what each one is teching up in. If you have that tech then when they are 1 turn or 2 turns away from teching up in that field, sell yours to them. I've made a bundle and always stay ahead in economics and technolgy by doing this every turn. (This is also something that should require spying, but, they haven't changed that either so use it).

Beating the AI on normal is as normal as the normal setting goes. hehe It all boils down to your economy first. If you don't have a great economy then you are going to fall futher and futher behind.

Thanks for all of your replies! It was very informative.