I think this adds a pretty fantastic "money sink" to the game that allows credits to leave players' hands in more ways than just buying ships.
However, I think it may be a bit *too* much to support a base. I agree that 1 person shouldn't be able to support a base without spending all of their time doing it, but a small group of people (3-5, say) should be able to keep one up without trouble, without spending all their online time on it.
The risk of failure is also too high, IMO--if a base gets blown up, you shouldn't lose credits that were in the base's bank account. They should go to someone. You're already losing the base, all the modules, and all the cargo--that's plenty of loss. Especially since you can't leave a base unattended for more than a day without running into problems. This is "discovery roleplaying," not "discovery make sure you log in for a couple hours a day or lose a billion-credit investment."
It would be nice if there were a way to "mothball" a base temporarily to reduce its rate of consumption, so owners could take a break for real life reasons. The base can't sell or buy anything and can't make progress on construction, but crew and resource requirements drop to levels that would allow a base to sit unattended for a while without blowing up.
I also think the construction requirements are way out of line with support requirements--there's a tiny initial investment and then a huge subsequent investment. That fools people into thinking that they can make themselves a base, so they do, but then they lose it because they're unable to keep up. Material requirements to make a base should be quite a bit higher--maybe make it so the initial outlay only gets you some scaffolding or something, and then you actually have to build the first core unit before you can do anything else.
Also, requiring materials that only can be acquired in Gallia is absurd and stupid. Obviously Sirians have been building space stations since long before they came across Gallia, so why are they required now? Plus, there aren't any materials on the list that aren't sold in Gallia, so a Gallic base construction doesn't require leaving.