Giantdad is designed for level 100 PVP. Most PVP happens around level 125 now. By dropping the Mast of the Father and instead using the Mast of the Mother, we gain about 140 health.
The only other thing that came to mind when I had to add these extra 25 levels was maybe get some Faith/Attunement and get something like WotG but it seems pointless and very un-Giantdaddy anyway.