I know, this is a favourite topic of mine at the moment. I read somewhere (can’t remember where now) that someone put a smaller chain wheel on the front, but with no derailleur. That means it isn’t possible to change the front gears while cycling, but it does give more gears. When I reach a hill and realise I’m going to need a lower set of gears for a while, I can manually put the chain on the smaller chain wheel and off I go. Genius. Wish I could remember who’s website I first read this on so I could give them credit!