What are the most beneficial tech trees to start with?

[False Prophet]

Should i just focus on all the colonization techs at first or expand my influence

[Full Melvin]

Diplomacy and science.. slip the expansion stuff in as you need it,and same goes for military..

If you can, and if you want to go toe to toe with other factions, fast track quantum communications on the diplomacy tree before you research new hull designs.. This will give you +2 on fleets for every hull researched after you get quantum comms..

Science track will open your resources so do not neglect it.

Check out my post called STFD (space tech for dummies). It works.. It may not be the ultimate oober strategy, but when your learning the game it will show you what you need without waisting time running to the wiki.

[The Mad Catter]

I try to colonize and expand as fast as possible so I can gain a foothold. So early on I hit the colonizing tech trees with some diplomacy tech to keep my peoples happy and up my Empire Cap so when I start gunning for military tech I can have a reasonably sized fleet. Though I tend to dabble in everything, those are what I focus on in the beginning. I'd say the tech that I trade for the most is the science tech. This is all in single player. I'm not sure how multi-player would handle that strategy.

I will say, I wish the developers made it a little more possible to succeed through one specific strategy rather than requiring you dabble in all of them. Like maybe if you conquered another faction's planet or even their entire faction, you gained a boost on your technology tree. Perhaps learning a few bits of technology, or lessening the research time on a few for example.

[Haldurson]

Depending upon the type of game you are playing, the expansion techs can become vital -- if you are playing a game with lots of star systems and relatively few enemies, or one where you have to expand via combat (eg. as the cravers) those 22% bonus vs. unhappiness due to expansion can become essential. I also like the techs to repair anomalies and try to get them as soon as they are cheap enough (when they take 3 to 5 turns to get, or better).

As far as the combat techs are concerned, even if you are playing a very warlike game, you should be a bit selective about which techs you need (sometimes you really need those techs to defend planets, for example). That said, increasing your command points per fleet can be even more important, and those are not in the combat tree, they are in the diplomacy tree.