Mars isn't a good option due to lack of magnetosphere.
Personally if you want to propagate life by shooting containers of RNA at different extraterrestrial plants.
It's an excellent option if you want to secure an incredible amount capital investment in a non-nonsensical pig of an idea - with visionary animations doing the heavy lifting as the most alluring lipstick known to man.
> due to lack of magnetosphere
Well, it's certainly one of the concerns there. After the lack of an atmosphere, biosphere, usable water...