It depends on situation and type of GP...In tight race for liberalism? Lightbulb! Race for Space... then Golden age... more money? Build shrine ...
Really, it depends... except when you play with variant like no lightbulb, golden age etc
For me, usually:
GA - culture bomb, golden age
GP - Shrine, lightbulb, settle, golden age
GE - rush wonders
GM - trade
GS - academy, lightbulb, settle
GSpy - infiltrate