Actually, I'd argue that the various factors you suggested aren't really as important as you suggested.
1. Refrigeration is quite nice for storing food for long trips. However, storing food is impractical for space travel. For every ounce you add, it takes that much more propellant to speed up and slow down the ship. For any length of time, people would need to be able to grow their own food.
Yet if we assume enertrons were created before the Day of Lavos (and I think this is almost definite), then food really isn't a consideration. The enertrons then, not refrigeration, are the key factor. Indeed, with the enertrons food is almost a nonfactor.
2. We don't know enough about Lucca's teleporter to know how practical of an application it would be. Does the technology have a limiting distance? Does there need to be a clear line of sight between the origin and destination? Does an increase in distance also increase the power requirements? If so is this a steady increase or is it exponential? Does an increase in distance also require an increase in computing power? How does the increase in distance effect the rate of error?
We do not see teleporters in Chronopolis or the Ruined Future, so this seems to have been of limited use.
3. Domes are useful, admittedly, but it really depends on what they were designed for. Are these for actually gathering resources or protecting the city (and if protecting, from what)? On one hand, the domes might only serve to catch carbon dioxide and other green house gasses for recycling and industry use. On the other, the domes might merely be a way to stop hail and hurricanes from damaging the city itself; useful, but worthless if one is trying to keep and atmosphere inside a city.
However, that is largely beside the point. Building a settlement underground, rather than entirely in domes, would be a better option for early colonization. Put a few rooms underground on the moon, equip them with an enertron, and a person might be able to live there indefinitely.
4. All the time portals closed at the end of CT. Thus, no data gathering.
5. Computers are nice devices, but not terribly critical. Sure, they can process information (thus critical for navigating a ship between planets for colonization), automate machinery, etc, but I am not sure how this makes it more likely that humans colonized another planet.
As a side note, we have no indication that there are any other planets in that solar system that are habitable. Even in Earth's solar system, there is only one planet in the Habitable Zone (Earth). Venus is too close, any colony there wouldn't have a practical means of heat exchange and even the machines would boil. Mars is a possible candidate, as it is right on the edge. If we assume Crono System is as lucky as earth, there would only be one practical location for colonies (the moon is not a practical location; people would be mining the cement for water!) and even that one would be dubious. If the Chrono System is just a little less lucky than the Solar System, colonization would be essentially impossible.
Now there might have been a few space stations (indeed, it is possible that Lavos actually did eradicate all humans on Earth and that the humans we see are really just space explorers that returned.