Some multiplayer stuff:

If you want to use something other than a colony capital, you can build colony frigate first, then continue with your other choice of capital. When the colony frigate pops out, move it to the edge of the gravity well so it can warp as soon as you're ready to colonize the target asteroid. Bringing the colony frigate out first to immediately colonize post jump, making for a smooth follow-through.

TEC early game (military) is two military labs -> LRMs, generally. Lately I haven't needed to go deep civ as TEC, just two civs for tradeports, although in a severely protracted contest, or as the "econ" player, TEC empire tree is incredible.

Will post again later as I think of stuff.

for efficiency..
buy 200 crystal on black market
increase your population once
buy 2 scouts
buy a crystal and a metal mining rig
buy a capitol ship factory
click the capitol ship selection, and tell it to build a colonizer(or whatever you prefer)capitol ship
set your scouts on autoexplore
buy your other metal extractor
as son as the capitol ship is produced, have it build a fighter strike squadron, train colonize, and send it to the asteroid that your scout found
develop 1 population on asteroids, 2 on other worlds just so that they aren't negative revenue

then either:
build 2 civilian labs
develop ice or volcanic depending on what the other scout found
build 3 frigates to send in after the cap ship to clean up on the neutrals while they are hammering on your cap ship that is colonizing the ice/volcano

or:
build 2 military labs, develop lrms, start building lrms for all you are worth
colonize desert, terran and asteroids only
attack your opponent with as many lrms as you can as soon as you find them