I like to go for Republic right away which means researching Alphabet, Writing, Code of Laws, Literacy, Republic. Sometimes an off path tech is needed on the way to Republic and I often choose the Wheel so I can kill off any AI civ on my continent with Chariots.
After switching to Republic, research will be faster. Next I go for Ceremonial Burial and Mysticism so I can build Temples in my cities and grow to size 4 (on Emperor). Next is Trade + Religion for Bach. Next is Democracy.
Meanwhile, cities will get a Marketplace so that they can grow and stay happy with some luxuries. My next goal is Railroad.
I avoid Pottery, Horseback Riding, Monarchy, Feudalism and Chivalry since they don't lead to any modern techs.