When I suggested the increase the number of subs from 4 to 8 and unlimited substitutions, my suggestion was dismissed.
However, I do not see the reason.
The number of subs is 8 in RU. Since RL is tougher than RU, there is no reason for RL to have smaller number of subs.
And, even if the number of subs is not increased to 8, there is still a good reason for RL to have a specialist kicker.
Rugby (both League and Union) are sports for large people, except RU's 9 (scrum half). However, if there is a specialist kicker, short/small people can play as a specialist kicker.