Production trap and teching Alpha for research sounds like a good hint, thx.
I somewhat disagree with alpha, if the point is to build

, just because there are more effective ways of gaining

- *drumroll* cottages. Production trap comes from doing stuff that emphasizes

over cottages. Looking at your screenshot, you have a too high focus on granaries (=emphasizing

! as without a high

-cap granaries are only good when whipping) and too few workers for cottages. I slow built every worker I think and cottaged a lot of green asap.
I also would not tech maths, just because it's relatively easy to gain via trade and you don't do much with it (+10

per chop is nice only when you need

). Techs like
monarchy, CoL, philo on the other hand drastically improve the way your empire functions and thus should be the bread and butter of your forcedly peaceful strategy. Monarchy is usually attainable via trade (AI will trade it even when they have a perceived monopoly over it) so after sailing and writing I went medi-ph and now deciding between self teching alpha, self teching monarchy or teching something I can use as a trade bait, which very likely would be CoL. Note also how SPI has great synergy with the religious branch.
All this applies mostly to the kind of scenario we have at hand: AI's are very far so an early war is not an option, but you do have them as trade partners (and boosting trade routes) so you don't have a need to rush towards astro-line. Under such circumstances, especially with SPI, focusing on winning liberalism feels like the most logical play to me.