First three are easy to get, last four are difficulty... must have a good thriving economy and research bulbs to be able to get that far and that is what the tech map is for.
Automobile is very hard to get and requires many many many other techs, cruiser/battleships might even arrive before then and battleships are a stronger attack unit, but usefullness is limited only to attack coastal cities but can also defend againt sea-invasion. Steel is easier to get than armor.
Industrialization is nice for factories and I believe it also gives access to transports which is also very usefull to transport more in case of naval/sea exploration/transportation needs !
I consider:
Best techs per category:
Republic number best economic tech, number 1 tech.
(best economic tech will still allowing warfare, strong food growth, strong economy)
Masonry best defensive tech, number 2 tech.
(best defensive tech, cheap to get, somewhat hard/expensive to build, good for defense for a very long time until invention of artillery.)
Artillery best attack tech, number 3 tech, best attack unit for ground warfare. (robotics also gives advanced factory/manufacturing plant)
Steel
Steel best naval tech.
Writing best research tech also dual function as attack tech with diplomats and spying tech with diplomats, cheap and fast to get.
Deploying caravans is hard against enemy AI

might be a waste of shields, do agree can help build wonders... I usually don't bother with wonders that go obsolete, though it is fun to have collussus at start for big economic influx and can last a long time till electronics... that will be a while !
Ceremonial burial, best religious tech, cheap/east fast to get and can get cities started somewhat above 3...
Railroad indeed best "speed up/connection/movement tech" almost infinite moves lol, depends if go to used or not. It's difficult to get though... bridge building might be more usefull is easier to get at least to cross pesky rivers which can slow down army approaches sometimes or deprive cities from more wealth !

it requires iron working... rail road is difficult requires steam engine, but how to get it ? requires many others... I can never really remember how to get railroad... I hope some day I will be better at the more advanced techs to remember how to get them in some kind of easy/usefull pattern that makes sense... at least this simplified tech tree makes a lot of sense... all progress immediately kicks the civ into high gear, no unnnecessary techs invented in between... so an exponential path to "economic/research/build" success...
Now all I need is some kind of simplified/stream lined army tech tree...