If you're just looking for a good Leo one, I'd try Azura or Sakura. The latter is probably better for Forrest.
Seconding Peri/Laslow, Selena/Subaki, and Takumi/Oboro (I mean hey, their supports set up Oboro's married ending, and there's her crush on him, and him actually not oblivious to it in their S. A+)
Beyond that, I don't consider anything so amazing that it qualifies for canon. I mean, I have my own preferences, but honestly a lot of ships could work for the remaining characters. Although if you don't like/go for Azura/Leo, try out Azura/Benny. It makes Shigure's "Snow-White-animals-love-me" thing hereditary, which is awesome, and Ignatius/Shigure don't have any conflicting supports (unlike Forrest/Shigure, who already have a non-sib support that gets overwritten)