You need to know what you need the compressor for. Is it for home playing, live playing or post recording processing? Each situation would require different settings and if ten of us from basschat used a compressor in the aforementioned situations you would have 30 didfferent settings exception would be @Dad3353 who is a drumner (the louder the better 😊).
We all hear sound differently so your ears are the best tool the find the answer.
Also , remember that there are other aspects that have impact on how you set up the compressor. If you do a little search on basschat , there is a thread or more about compressors in general.
I own TC spectracomp which is extremely versatile. Currently sits in the box but I was never dissapointed with it's performance.
Horses for Corses.