So I've been thinking about how Strength and Speed limit removal should work and I've come to a conclusion; a character would need traits like yours multiple times for each Grade in Speed and Strength they want to overcome. Since you want Ambrogio to push into B Grade for both Strength and Speed, your Traits would look like this (you can change what you call them or how the description is worded, but the basics need to apply);
[b]Character's Name:[/b]Ambrogio Genio [b]Name:[/b] Undead Muscle B [b]Type:[/b] Racial [b]Description:[/b] This trait raises the cap on the character's [b]STRENGTH[/b], allowing for B-Grade Strength.
[b]Character's Name:[/b]Ambrogio Genio [b]Name:[/b] Undead Speed B [b]Type:[/b] Racial [b]Description:[/b] This trait raises the cap on the character's [b]SPEED[/b], allowing for B-Grade Speed.
So if you want your character to reach A-Grade Strength/Speed, you'd need these Traits a second time. I know that would be a lot of Traits to get Strength/Speed to S-Grade, but the benefits of S-Grade are very nice. Ambrogio is good for now since you only want him to reach B-Grade for Strength/Speed, but keep this post in mind for future Stat manipulating Traits.
So yeah, just edit the Traits to more or less match what is in the code.