One of the barriers to entry for the Oathbreaker format is that it is difficult to easily build new decks.
It is unlikely that any constructed format is conducive to a simple migration into Oathbreaker.
When I first heard of the format, my idea was to take one of my flagging commander decks, replace the commander and the Sol Ring, and shuffle it up.
The fact that there is a hard-enforced sixty-card limit does remove this option.
Is there a reason why the deck size couldn’t be (like most other constructed formats) “At least sixty cards, including Oathbreaker and Signature Spell?”
What is the rationale for prohibiting 100-card decks? Does it make Battle of Wits too powerful?