I'd be inclined to not do the extension for Yelich. At the time of the extension, Braun was a perennial all star and never played less than 150 games. And he seemed to have the body type that would age well.
Way too early hypothetical: So Yelich will be 30 at the end of his deal. Braun was 31 at the end of his similar first deal. Would you give Yelich a Braun-like extension (5 year/$100 million)?