System recommendation smart citizen measuring noise and air quality
One form of common wisdom in life is: only build it if you can't buy it.

My focus so far is on noise and air quality, which I want to measure over time...

This seems that you're more interested in the environmental issues, rather than the electronic ones. So buy/borrow or purloin the requisite components. You needn't reinvent the sensors/controllers unless that's the bit of interest for you.
Note: Arduinos and Pis are relatively easy due to the massive global user base. Just ask, it's probably been done already :-)
And Hi.