Avoid toll by time savings

request for a new feature, user would be able to enter the time(minutes) saving tollerance for using toll. for example : it toll using saved up to 7 minuts do not plot directions using toll, only regulal roads.
every day i use routes to change this on my app. this is because, for me, saving 2 minutes of driveing time does not worth the toll payments.
thanks
tsahi.