3 things:
1. Who's this "we"? If it's not the wife's idea your time might be better spent shopping for a more comfortable sofa.
2. After removing the rarely used chainrings, what do you think you will have accomplished?
3. I'd choose "b". The nice things about moving the big ring to the middle position is it's cheap and relatively easy to do (you'll need shorter chainring bolts), it'll work fine, and it's easily un-done.