There is no way to make them equal in lenght, since some routes are more popular than others, and it also depends on polls. You can see what routes are updated at the change log.
Winterlook
2017-06-01 22:25:09 +0000 UTC
I must admit to some annoyance that the game follows nigh-invisible 'tracks' of differing length. at what point can one depend on getting to the -actual- end of a build regardless of what path one follows? Or at least let the trails have -approximately- equal length? any time soon?