Do we even want the Isolation Event anymore?
This has nothing to do with the tech tree, but it's important to think about.
from my point of view the tech tree and the game eras are inextricably linked. hence I have renamed this thread to incorporate both.
if a lengthy discussion of the number, quality, and type of game eras is to ensue we could of course start a new game era thread. however this way we permanently document from the start what overall parameters were used to constuct the tech tree.
vanilla Civ 4 of course has four eras, though none intended by as transformative as an Isolation Event.
As far as the tech tree is concerned, I love the first era and the second isn't bad.
If we change the scope of the mod then we'll need to alter the techs as well, but the "Survival" era isn't bad, except for how easy it is to actually survive.
this is the first time I have read anyone in these posting forums say that the first era of the SotM mod needs to be "very tough" to survive. this new concept needs a lot of exploration in order to flesh out.
for convenience we will call this idea "Disaster World" or DW for short.
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does this mean some of the starting civs will usually not make it in DW and die out fairly rapidly?
the first corollary to the DW concept that springs to mind is that DW rules out barbarian civs. if the moon is that harsh a mistress they would never be there at all - unless of course they were aliens descending from spacecraft.
if the colonists were struggling that much this would imply that they would not have the resources to change their civics until after the isolation event (IE).
I am not sure what player reaction would be if theirs was one of the civs that did not make it. would it be possible to start over (unlike vanilla Civ 4)?
in the past there has been discussion in these forums of meteor storms, solar flares, and other disruptive events. the DW scenario would by definition have to have a lot of these types of events. even after the IE such disasters would always loom and there would have to be techs available to research that would prevent disaster from striking on a random basis.
there has also been past discussion in these forums of the idea of using subways instead of roads due to the moon's harsh environment. this would also be a natural corollary to the DW scenario.
before I ramble on more about DW I want to make sure the whole development team buys into the concept of a rough start.
this would of course mean a virtual rewrite of the code from the ground up, and so is not a choice to be made lightly.
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at this point if we are indeed working from a blank state, we need to propose competing ideas for the various eras of the Moon. we also need to rapidly decide if Aliens will actually be a part of this mod. for lack of a better description I now will call the Final Era "Alien Event" (AE) since if aliens are encountered, the last era will be the most important in terms of contacting them.
to sum up, the scenario for a set of three succeeding eras currently on the table is
DW -> IE -> AE
if the development team buys into this, then we can start fleshing this three era scenarios out. however I am sure the other developers out there have other ideas about the number and nature of eras for the SotM mod.
my own preference is definitely for IE and AE. I cannot yet envision how a viable DW would work.
re: barrenness on the Moon . . . 
