The problem of not having a magnetic core I believe will be solved by towing ateroids rich in iron down to Mars. How this happens is interesting, but we can probably change the trajectory of asteroids in the Kuiper belt or possibly even the rings of Saturn and set them on a collision course with Mars. But there might be a way to do it that is less violent. Then, by drilling a hole into the core which we can use to send down trillions of drilling bots into the core to create a large spherical hole to house the molten core, and then using the same hole to send entire melted asteroids in liquid iron form to the core. If the water at the poles is not enough, we can also tow ice asteroids to Mars. Getting the water down to Mars could be easy. Have the ice asteroids go in orbit over Mars. The Sun will melt the asteroids, raining down water on Mars. All of these asteroids being used to build Mars will also raise the weigth of Mars, getting us closer to 9.8 m/s^2 G. The rock we drill out of the core can be used to build living structures, cement and steel are easy with these raw materials. Nothing will be wasted. Eventually, a timed sequence of thermonuclear devices will likely be needed to ignite the molten core and set it spinning, after which it might create a self-sustaining magnetic field. We don't want to do the first attempt on Mars. We need a mock system where we can test all the steps that we have the precision to achieve the goals. Balance ambition and precision. A totally dead useless planet or moon far from the sun can be used to do the magnetic core part. The water part will probably have to be done on Mars itself with no testing.
Journey to the Center of Mars? Time to flesh out this SF fantasy and sell on Kindle Unlimited when complete.... Take fact and weave a fictional story (or series) out of it...
Curiosity takes a picture of Earth from Mars. Just a pinpoint of light from a relatively close planet:
Seems you would enjoy the work of Jaque Fresco over at The Venus Project - he has been a visionary for many years now attempting to achieve some of the things you are mentioning regarding mars here on earth but obviously is met with great opposition! Perhaps Mars would be more accommodating to his dream world...