There are some setups that can change the game if you exclude some roles. One that comes to mind is one suggested in the state of the beta thread where if you don't have spies, party host becomes more important.

You could make a save where spy is impossible, but most people won't notice(as you need to analyse the top role cards for missing roles). Perhaps taking the work out of figuring out what's impossible can consistently allow for more unique saves that exclude entire roles.