The issue with Monaco is the cars are just too big for that track now. They need to modify it somehow. Atleast back in the 60/70/80/90's the cars were small enough to actually get alongside and pass, that's near impossible now.
The skill and bravery required to drive around it as fast as possible is exciting, but the actual racing isn't.
I remember somebody on youtube (chainbear I think) mentioned the possibility of a joker lap style extension. If you're being held up by another car then you can take your joker lap (an extra part of the track that adds like +15 seconds) so that you can make up the time on the track. Eventually the person that was holding you up will be forced to take the joker lap too and you will overtake them.
They showed how in Monaco there is an extra part of the city they could use as the detour. I guess it just depends how much they want to jazz it up, or whether they're happy just having it as a booze up weekend.
I know the drivers enjoy driving it, but the race is all about qualifying and not crashing.