Just like Robotic companions, I believe Beasts should also get a separate, moddable "weapon" to mod (Fangs for Kubrows and Helminth Charger? Claws for Kavats?)
Here are some of the pros and cons from me.
1- Having more room to place and separate mods (Bite, Maul, elemental mods, etc. will go to the weapon slot) encourages further customization in light of the new mods introduced in Fortuna (set mods, dual stats elemental mods, Fetch...). You'll also be able to put all the pet's