With my kid I had to tear out all the carpet (he stayed for the week elsewhere during that process. To let everything settle, then my washing down the walls/ ceilings/ furniture (aka where stuff had settled to). I then painted the subfloor until I could afford real flooring.
It doesn't sound like you need to go that extreme.
BEFORE I tore everything out, the BEST I found wasn't actually a vacuum cleaner... But a steam cleaner. As it didn't blow up dust, and the water trapped everything. And I mean evening. Way better than the best of paper or carbon or whatever kind of dry filter. Booya!
I had to do that daily, however, and the machines only last about 6 months of daily use. The carpets really stood up, though, and that surprised me. I was always told more than a couple times a year would destroy them. Nope. They did great.
ANYHOW... That would be my recommendation: a steam cleaner once a week instead of a vacuum if you're worried about dust. Bissle worked best for us (again, rough 180 use lifespan). At once a week, that would be about 3 years.