Along the course of play, I've acquired some seemingly miscellaneous objects - a 'normal watch', several rings (labelled brass ring, fancy ring, and so on)- do I sell them or will I need them later on?
It looks like rings and watches (among other items) are used solely for making money. From this Steam discussion thread:
Rings, fancy and normal watches, car stereos, morphine, prescription meds, and such like are vendor trash. They exist purely to make you money. Raising your Haggle feat increases how much you get paid by vendors and lowers the price of stuff they sell you.