Most fish will die after about 5 / 10 minutes out of water...so no bashing maybe necessary..
Catfish are different...I do them fast..quick cut behind the big pointy sticker..cut skin around fish...slit belly..and skin fast..fillet..and cut off head..the other species will die after 5 / 10 minutes out of water..
Those I scale...and fillet leaving the head on. less than 45 seconds a fish.

I leave the skin on these fish.