Hadza

Asteroid redirection is 100% possible with current tech, just needs more rockets, some space telescopes and tracking centers, others are TBD.

I don't think a "solar expansion limiter gigastructure" is "relatively simple"

It's simple in a sense that it requires a bunch of large dumb things operating together (mirrors, some kind of heavy magnetic current, etc), it's not complex, see, although gigantic. But then comes orbital stabilization issues and a bunch of maths... well yeah, it's simple at least in a sense it doesn't require some special physics like warp drives or something. In cases like these it's good to distinguish new technology from new engineering, where the latter is iterations on known tech while the former is something completely new.

But maybe there's a possibility of a space-faring technology-lite future

I would say we shooould orient ourselves for space and expect to never find any FTL tech, including communications. Even if colonizing with sub-light speed, it won't take neeeearly as much time as you might think to even colonize the entire galaxy if you go the "self-sufficient colony capable of producing more colonizers" route because of geometric progress.

I see going super-spaceborne as a necessity because of this: we're slowly increasing the potential longevity of our species and civilization thanks to knowledge and gain ever increasing knowledge of our Universe's inner works. If fundamental questions like purpose and reasons of existence can even be answered at all, it will take a lot of pondering for us to get there. A lot of pondering that will definitely NOT happen if we die. And maybe our Universe needs us to answer them, either metaphorically or metaphysically. It took us absolutely incredible luck (it really is amazing, I can try to elaborate if you don't know it already) to even get to the point of being able to answer questions. What was it all for, to just impotently wither in a couple of million years? I personally just can't buy it.

I never was religious, but fairly recently I started to feel a sense of much higher purpose and I just can't allow us to sell ourselves short. I really don't want to be subsumed by AI or snowballing genemodding though, at least not yet, I think through simple eugenics and perennial way of living we could become all that we want to without the threats of extinction spiralling. Maybe we will reach a point where our flesh will be too weak to keep on pondering the ever increasingly complex questions, or the Universe will become so old and barren it will be unable to provide our bodies with the energy they need and we'll need to morph into something else, but until that very distant point, we should do everything in our power to keep our human form. Our genes are selfish for a reason and we should keep it that way until we can definitively answer if we should shed them.