I usually do conventional starts as well.
In my current game for starting settings, I set the game to generate pre-TN races only, and zero starting NPR's. I also turned off all spoilers except precursors. The plan is after exploring a few systems out, to turn on swarm, and maybe regular TN NPR generation, and then later, invaders. This lets me get my nice organic development without getting stomped by a full NPR 1 system over.
From a more RP standpoint, I create ruins on Mars (re-roll till Ruined City or better), starting pop at 1 billion (gives 10 labs), and zero shipyards. I also delete the starting 5 maintenance facilities, DST, and academy so I start with nothing but conventional industry and the 10 labs. I also instant research the basic 'Trans-Newtonian Technology' since there aren't many interesting decisions before that.
I also have a few 'tricks' on a conventional start to make things interesting. You can build a PDC with an ICBM launcher and fire control (if you don't start with ICBM bases), and once the first reactor tech and geo-sensors are researched, you can build a size 24 probe that can reach out to Saturn. This lets me discover the Mars ruins before even having a shipyard built. A few fighter factories lets me build a conventional-engined shuttle that can take a xeno team to Mars.
For the wiki, somebody doing a single empire conventional start for the purpose of learning the game, I would suggest similar. No starting NPR's, conventional only NPR generation, no spoilers, and stick a ruin somewhere in Sol.
Starting goals would be to geo survey sol, find the ruins, send a xeno team to the ruins, establish 1 or more colonies (Mars, Luna, other), get construction brigades to the ruins and perform recoveries, research jump theory and grav sensors, grav survey sol, build jump ships, and explore 1 or 2 systems out from sol in all directions. At that point, maybe turn on precursors/swarm. If you find a conventional NPR, maybe conquer them (learn ground combat). Establish 1 or more colonies outside Sol. Find some precursors/swarm and defeat them. Explore more. Then, when ready turn on TN NPR's.
Would it be worth writing up a walkthrough based on something like this?