My build is technically a 1-offensive-button build (Savagery) aside from the permanent “pets” (Wind Devil). Just re-spec the defensive skills (Wendigo Totem, Nullification, and Mirror) into something else like passives, and decide between the axe or crossbow/rifle if you don’t like weapon switching.
A warning, tho: Callagadra is super dangerous to facetank with just the rifle, much more so without Wendigo Totem and Mirror.