For whatever reason, the PG position has not been the most crucial position in the finals in recent years. Taking a look at the last 10 Finals MVP's you got:
Pierce, 2x Kobe, Dirk, 3x Lebron, Kawhi, Iguodala, and Durant. All those players are Wings and Swings who play both sides of the court. Only Kawhi, Iguodala and Durant won the title while having a pg who made the All-Star team the season they won it (and of course Iggy and Durant both played with the same All-star guard in Curry).
When you really break it down Parker and Curry are the only 2 All-Star point guards with at least 1 ring in the last decade. (You may be able to throw Kyrie in there since he was hobbled in the regular season, but put up 25-3-5 in the playoffs the year they won the championship).
With that being said, it might appear that Hayward would need to have a huge season in order for the C's to make serious noise. If Kyrie makes it to the C's I wonder if he could truly be the #1 option.