Venus is far too hot to be useful for anything besides dirigible cities, and what are you going to do there except sightsee the yellow clouds? Maybe it could be terraformed to something livable, but that would take a long time. If that could be done though, it'd be a great place, since it's close to Earth's size and gravity.
Mercury is too close to the Sun and too hot. You could put a city on the dark side, but the city would have to move constantly to stay on the dark side.
The asteroid belt might be useful for mining, as would other places farther beyond, but anything that far out is going to be very cold, because it's so far from the Sun. Also, the Moons of Jupiter are bombarded with massive amounts of radiation from their planet. And all those places have horribly low gravity too, which probably won't work well with human biology, unless perhaps we genetically engineer ourselves to fix that.
Space exploration is great for science and maybe resource extraction, but I just don't see the point of colonization except for a couple of somewhat-convenient places, at least not in this star system. I really can't imagine an "empire" across this solar system. Now it would be really cool if we could explore the TRAPPIST system and maybe find livable worlds there.
If you meditate on this you will see that the amount of gumption doing this, especially when info was not so easily begot and Safeway didnt exist... jesus - humanity was REALLY tenacious in the past. So, if given the opportunity to go on a craft to mars with even a single digit % survival probability - I would do it, if anything just to honor those who have done the same in the past...
Even with your "jump on a ship" bit, European exploration of the "New World" was very expensive and required investment from wealthy patrons. It wasn't something a small group of adventurers could just do on their own.
If you can fund a Mars colonization mission all by yourself, then more power to you. But I just don't think it's possible, at least not any time soon. As a species, we haven't even managed to do any better than landing 3 men on our very nearby Moon for very short missions. We have zero experience in building and living in actual offworld habitats. It's never been done, not even in the one place where it's so close by that a rescue mission wouldn't be hard to do. The closest we've come is Biosphere II, a glass building in the Arizona desert, and that was a big failure.
It's too late to edit this, but I just want to qualify it: we have zero experience building and living in habitats on other celestial bodies. A small space station in low-Earth orbit within the Van Allen radiation-protection belts doesn't really count.
Funding be damned. No one is asking you to work your arse off Interstellar style to fund a secret program to fund humanity and get us out of here. And no-one is asking the US government to pump a trillion into setting up colonies out there. But it will happen - and there will be commercial starts to it - asteroid mining, with initial small numbers of support personnel up there, then maybe a few habs. Maybe it will take generations; or maybe we'll be wiped out before then. But it is either part of the inevitable march of the story of our civilisation; or there won't be a civilisation to talk about
Besides, if it's strategically placed, it could easily threaten Earth with kinetic projectiles if Earth's political systems attempt to take control of it. Military units inside a deep gravity well have an enormous disadvantage to those outside the gravity well.
These rockets are far superior to their ancestors. With orbital factories around earth, and regular deliveries of colonization supplies, the network is vast, complex and efficient.
Starting with battery manufacturing on earth, all the colonization components required of earth are delivered to the orbital factories where humans and robots work in a beautiful synchronized effort to prepare each packet to Mars. Batteries and other components are delivered to orbit. They are then constructed into the various machines to be delivered to mars on the massive Falcon-33s that will haul them to Mars.
The autonomous Tesla Landers are quite complex, they have impressive batteries, but its their job which is more impressive.
Once orbiting Mars, the payload shall be unpacked and deployed to the surface, where they will continue the construction of the massive solar arrays which already have a large contingent of batteries to slurp up the solar energy and store it for all the other needs of the build-out.
The project has been going on for decades, but we are starting to see some serious results in this phase...
The original idea was laughed at, but it was all backed by sound science and a simple phased approach:
* Develop seed infra at home; Batteries, rockets, robots
* Consumerize these to fund later phases
* Proof-out orbital autonomous delivery services via the ISS
* Commoditize space tourism, popularize it with celebrities
* Exploratory missions to Mars
* Develop orbital manufacturing capabilities, where supplies can be delivered autonomously
* Build Ultra-heavies in orbit, modularly to avoid launch costs from surface (required tethering technology to be developed)
* Deploy communication relay probes between spatial bodies
* Deliver initial robots to surface of Mars, they prep for solar install
* initial solar install to feed robot population already on surface
* Add batteries
* further infrastructure to follow, but with a working autonomous robot service group ready to build out
We are now at the deployed battery stage, the Organization is now preparing the life support systems for long-term human colonization, and within the next 25 years, we will have a permanent Human Civilization2 on the planet Mars... perhaps, Again?