IMO, whatever you are used to. I've used the same rifle for 8 years, Falcon FN19 .20. In that time I've bought,then sold again several others but when it came to the crunch they stayed in the cabinet and my old faithful came out! The only exception is for close range ferals when i want low power to avoid damage to buildings. Then i use a little Crosman Ratcatcher. Looks like your doing ok with what you've got!
Good hunting!