Yes, crosscut and skyliner are good fillers.
But I prefer using doppel skills during the extra time while having PB15 and Gungho15.
I used to be HL3>barb1 before the change but I’m much happier with SW3.
My opinion may change when we get higher defense monsters where we need skull swing.
Kunai is also spammable now making it a good filler, you’ll have enough skills in the end.