Hello again,
First of all please do not compare adding new content to the game with a pointless modification to a map. Going from Cerulean Pokecenter to Cerulean Cave does not take more than 30 seconds. Altering the map and adding a ravine, a bridge, a fence or anything else serves no purpose other than to save you those 30 seconds. You have a nurse already, you can kill pokemon to cover her cost and you have to go back to the cave again once an hour or so after getting a new team when you are done training. So this suggestion is not going to be implemented and this thread is being locked. Have a nice day.
Kind regards,
StripCoffee