I want a Moon Base so that I can order books and things from Amazon.luna.sol and get them here in my secret base on Charon that little bit quicker.
Actually, we need a number of things (and I'm sure I've said as so in another thread, recently... Maybe it wasn't this particular forum, though). Earth-orbit habitation, with both LEO and Geostationary/Geosynchronous presence if we don't have Space Elevators, yet and can just stick with the latter (but then we also have 'counterweight' bases). Then Moon-orbit habitation, although Selenosynchronous orbits might be a problem, for various reasons) which could actually be of a Very Low Moon Orbit nature if we're feeling adventurous (but wouldn't help with the trans-lunar transfer, any, due to the need to build up/bleed off 'horizontal' velocity, even while the height change isn't so much... in fact, it might make it significantly harder to coordinate[1]).
Moon-surface habitation will not be as good for the human body as Earth (or Mars) habitation, for normal biology, but it will be better than nothing and most of the jury-rigged methods used in freefall habitations can be adapted to assist.
The big problems are radiation/etc. There's problems at LEO. There are problems at Geosynchronous/stationary heights. In lunar orbit you'd basically have to build up shielding from scratch. On the moon? Well, you can dig... And send material (either alongside more traditionally usefully processed material or as part of pre-processed material that you're finding it best to separate in zero-G anyway) in order to paste around the stations (or the 'lifeboat'/shelter sections of such stations) to create/augment their protective layers. Easier to get that stuff from the moon.
Of course, when we've got the asteroid belt under our... ahem... belt, then the prospect of hauling asteroids around could price out of the market the "from the 1/6th g well of gravity" moon for equivalent materials. With big enough ones being hollowed out (and any less-useful stuff pasted onto the outside) to create viably shielded residences, although I think they'd just do that out there in the belt to create pirate coves mining colonies.
When it comes to "how long to get back to Earth", I think that's a red herring. Antarctic bases are self-sufficient. The doctors/dentists/plumbers/ double up on research duties, and researchers have at least some training in doctoring/dentistry/plumbing, in general. If there's a health problem in LEO, say (in times past) on the Shuttle[2], they'd be looking at aborting the mission early and bringing them back. But that's like a patrol boat off of the coast of your nation. Compare and contrast with what happens in ships in the middle of the ocean. You make do. And sometimes making do is not enough for the individual. Or, indeed, the team. (c.f. Scott's expedition to the Antarctic... perhaps foolhardy, for a number of reasons, and some might say pointless given its lack of success against the Norwegians, but without trying there's no doing... Unless you're Yoda.)
There will be deaths in space. So far, deaths in space, and various related ones, have been full-blown accidents[3], and those will still happen... While we do not need to become actually blasé about them, it is a mistake to throw the anchors on every time it 'something' happens. Medical emergencies can be planned for and the very best provision made, in case the very best attempts to prevent them coming up in the first place have been unsuccesful.
Anyway, I say we need to be elsewhere than Earth. Eggs, baskets. Nuff said. (A 'civil war' throughout the colonies and homeland of the solar system is a negative thing that could happen, but at least we tried.)
[1] Although I could see spinning space-tether technology being used... But without the magnetic-field/solar-powered-current re-boosting/retarding technologies that Earthly-orbitting transfer tethers would use you'd need some actual reaction mass to adjust and compensate for the gravitational potential transferred in and out of the system.
[2] What's the old story? American space pioneer shows his Russian opposite number around the Shuttle mock-up and shows him the fancy defibrillator and medical equipment, specially adapted with straps and things to work in zero-G, etc... "And we spent a lot of money making sure it would work". Russian: "We only ever send healthy people into space!"
[3] Decided to look it up. According to the source I'm looking at, officially "space deaths" total: Seven deaths post-launch, three deaths through atmospheric loss, seven deaths through re-entry disintegration, one parachute failure. This does not include training flights or the three initial Apollo deaths during that take-off rehearsal. I thought there was an additional death through loss of atmosphere during re-entry, but I can't match that with the list of all Russian deaths I have.