In my mind the multiple would go anywhere from 2.0 - 0.8. Of course in my world voters would hold their reps responsible for their votes and corruption, so I'm just whistling in the wind here.
Eh, less salary means only wealthy ppl can be in congress. What we need is for a lifetime forfeiture of all assets other than those provided by the state. You join congress, you get room and board for life, but nothing else.
We already have a very deep problem with the rich class in congress, with very few upstarts. They above would cement their hold on our democracy permanently.