I tend to turtle in Sol (mainly to avoid situations like Paul's), putting my efforts into improved research rate, terraforming, industry (mining, construction, etc.), and financial centers. Then I crank out a bunch of research labs and terraforming ships, start building up weapons tech while terraforming Mars. When I'm about a year from finishing Mars, I start building my colony ships. At about the same time that my colonists are starting work on Mars, my survey ships make the jump over and start working on those systems. If there are any terraforming targets, I send the TR fleet to those each in turn. By the time those surveys are complete, I usually have enough miltech to lay down a destroyer design that can stand up to Precursors, and I start laying those down. From that point on, I blow through the miltech as fast as I can, with a few dedicated Con/Log/GF teams working on those things.
For me, the most important part is upping the research rate early and churning out more labs. More research means you're going to be better prepared for things down the line. The Invaders might show up thirty years in the future; they might show up next week. I like to be as ready as I can be.
But why would you want to
avoid situations like mine? That was a lot of fun, battling the four precursor ships with my little low tech fleet was way more fun than sitting there colonizing mars and mercury for 10+ years could ever be.
Turtling up in Sol is safer, but it's boring. I like to go out and explore the universe as soon as possible, make use of ruins I find for tech advances, establish early colonies via infrastructure, and battle it out with alien life while they still pose a real challenge. It's not a real fight if you don't lose half your fleet in the process
If it was adjustable I'd make ruins with precursor guardians and swarm and such more common, it makes exploring the universe interesting.
Techs I got with my starting points:
Research rate 280 (10k + 5k for 240): 15000
High Density Duranium armor: 2500
All the jump drive basics, + efficiency 4 so I could make cheap jump tenders for very early exploring: 14000
Ion Engine and the Ion missile drives (speed is good): Total of 30000
Fuel efficiency .8: 3000
2 tiers of Reload Rate, Agility, and Warhead techs for missiles: 18000
85 mag ejection, 80 efficiency: 5000
Active and EM sensor techs: 12000 for tier 2, I think I might have put 20,000 to get the 3rd tier of active sensitivity.
Grav sensors: 2000
Then I spent about 5k or so on developing the various components. Engine, launchers, sensors, fire controls, magazine, missiles, etc.
Forgot where I put the leftovers. I think I got small fuel tank? Those are handy for topping off a design.
This way on day 1 using the fast OOB creation points I can have a survey fleet out exploring the galaxy and a defense fleet training for the inevitable bad guys. I also develop a basic jump tender right from the get go, military jump engine on a commercial ship. I try for 4-5k tons depending on what I can afford, and build my early military ships to match. My early exploration ships are grav survey sensor + military engine and some fuel tanks, basic 750 ton design that goes 4k with ion engine. Cheap and expendable. The geo survey are bigger due to using a commercial engine, usually about 1800 tons with a speed of 4166.
I'll set up one of the SYs it gives me to build a constant stream of warships to bolster my fleet while researching better techs, never know when having 20+ warships can come in handy.
I'll get a scientist in every field that I want research in and put 1 lab with them so they can build up their skill faster. Then I put the rest on getting research rate and mining rate and such while I explore and fight using my low tech fleets. If I hit a real snag I'll focus research on something to improve combat effectiveness, like missiles or whatever - but generally I do a balanced approach - level or two of research rate, then use the better rate to get the next tier of other techs. Then more research rate, and so on.
-edit-
Ooh, I captured the two DSTS bases in the system where I beat the precursors. No ruins, but there are 900 of those nasty size 4 missiles. Just my size! My fleet just got a new toy, I'll put them to good use against the next threat I face - have all my ships loaded with them now. Too bad you can't disassemble missiles for tech, they're twice as fast as mine with a 50% bigger warhead and a bit better hit chance to boot - could probably pull some good tech from them if it let you.