Over what period of time have you caught the above listed species?
Are the 3-4 different crappie sizes in the same season from this pond?
If the crappie are achieving 12-13" consistently you don't have a crappie problem and if the bass you are catching are not skinny with sunfish present, my question would be size structure of BG/GSF/RES or whatever it is you are calling "perch" as there may be a clue, or red flag right there. Do you catch many very small sunfish? Tell us a bit more about those.
As posted above, fish can become very hook-smart in a pond but it may be more important to know what your expectations are and how many times you fish a month.
If you can add a few more details, maybe we can add something more to this.