Take time to learn what the techs do, once you understand which line of tech does what you can lean on which tree line you need to win.
If you plan on wheelin' and dealin' with the other races or try to start wars between them, you need to focus on diplomatic techs ( yellows ). It will also help with trading techs and selling techs if you have that enabled.
Should you be inclined to win by conquest, you need to pick one of the 3 trees of weapons and focus mostly on that tree. Having lower level tech of multiple branches is not as effective as one highly specialized branch.
When I am deciding what to research next it also helps to think of what your longer term goals are. Having trouble with morale or money? Research a few entertainment techs, allowing you to raise taxes and build new improvements. Or, look at the planet quality techs which allow you to add more tiles to the planets and increase population cap and growth. Want to speed up research to lock in the tech advantage? Follow the research techs ( blue ) to upgrade your research facilities to xeno labs and discovery spheres etc. Need to start making a better military? You could also consider following the manufacturing branches ( orangish ), so your military and social production ramps up allowing you to make ships faster.
Anyhow, Im tired of typing, hope that helps a little.
Insert Sig here cuz I dont know how to.(5+ battles won,normal,good,random mil. rank)
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