By 3000 we will likely have cities on Mars. Will our decendents make regular trips back to Earth?… Probably not.
Future humanoids, whether living on Earth or Mars, will live much longer than we do now, largely as a result of anti-aging engineering which is heavily reliant on genetic engineering, nanotechnology, stemcell implantation and cybernetics. The Earth based humans are, however, likely to live still longer than their Martian cousins due to the environmental hazards in getting to and living on Mars.
Certainly, biosynthetic humans [which parts need to stay ‘natural’ to remain human??] are likely to be walking the planets well before then.
The Mars humanoids, after perhaps 700 years of habitation, will have novel features, some organic and some synthetic. Some shielding against cosmic rays will have been acquired [though skin will become paler], plus further cranial enlargement and skeletal body mass reduction [more than on Earth due to the lesser gravity]. Quite a puny, weak look really. If atmosphere has not yet been rendered stable enough to maintain adequate atm pressure and O2 pp, then further cardiorespiratory modifications will have been incorporated into the future Martian. Thus the Martian cities will at some distant point cease to be sealed, such that taking the air on a Red Planet boulevard is a time to strut your stuff.