Great BP and high crit rate but sorta bad acc.
Covers Rock, Ice, Steel,Dark, and Normal types.
a bit less BP but much more accurate then Cross Chop.
Covers same types as above.
Great BP and Acc.
Covers Rock, elec, steel and poison types.
Decent damage and great acc.
Covers Steel, Ice, Grass, and Bug
These are the most viable filler moves for him and as for the choice I would go with Crosschop. Cross Chop as amazing Coverage and Great Damage for electivire but pretty weak damage. You can choose Brick Break nstead if you wanna play it a bit Safer.
Edit: Fire Punch isnt as viable in NU due to it only hiting 4 pokes Cross wont hit for SE
Hope I helped