[@Willy Vereb]
Sorta, just set further into the future with more infrastruture development & biotech.  It isn't meant to be space opera as it is meant to be more exploring what sort of societies would form after sol has been lived in beyond earth for centuries and the politics, conflicts and way of life which come from that.  Imagine what sorta culture would develop after centuries of living in asteroid habitats!

Think of it this way, it's meant to be in the further future mainly so there is time for new cultures and societies to develop in the solar system distinct from what exists today and give time for infrastructure to age.  In terms of colonization, with the centuries of time what you see is the development of biospheres in large habitation complexes.  Earth also has a biosphere with lots of modified life forms.  

Alien life wise I am a bit loose, in that I am likely to allow complex life on Europe that has distant genetic relations to us and whatnot going with a panspermia interpretation that life originated in the kuiper belt, not Earth.

This does allow for one to make new human species or uplifted animal species alongside AI, which means one can rapidly have uplifted octopi stand in for mollusc aliens or some bioengineered arthropod stand in for insectoid aliens (thanks to high oxygen & low gravity habitats).  The ecosystems are within large habitation complexes, be it under the surface of mars, in a sky habitat in the clouds of Saturn or inside asteroid habitats.  Really, wherever you feel would be logical for a habitat, there is a habitat.  In short, avoid terraforming on a planetary scale and instead focus on making habitation complexes.

In regards to technology, just avoid advanced AI (the sort that manipulate reality and act as god stand-ins), star lifting, worm holes and tech in that realm.  A dyson swarm is fine though, since that is just a bunch of satellites around the sun.  Basically keep it within the early type-I range. 

I may allow for one naturally occuring wormhole connecting to another star system, but it has to be a naturally occuring one we overlooked somewhere 50 AU or so out where we can place world types sol doesn't offer (mainly ocean planets) and give some space for alien life to exist beyond of subglacial seas or under rocks.