re freewheel life-- when I encountered a bike where the freewheel started to show "gumminess" behaviour, ie not as good freewheeling, I've taken them off and dribbled some thin oil down into them while they were on a rag or newspaper and I'd turn it often. Let sit, run some more, turn , turn etc and was always suprised by how much grit came out with the oil.
Was always better turning or freewheeling afterwards, so this might be something to do once in a while to help keep the innards more free of stuff

but perhaps other real mechanics have an opinion on this.