I use sunfish for bait all the time. Great bait for catfish and bass in the hard fished retention pond across the street from my house. Just catch medium sized sunfish and use big circle hooks. Works like a charm.
I have a similar funny story. I was fishing from shore in a sandy bay in Clark Hill Lake on the Georgia side. I think I was fishing for catfish. I see a nice size striped bass cruising around. The only thing I have in my box that is close to big enough is a 3" silver spoon. So I tie it on and toss it out and the striper disappear into deeper water. I keep casting for awhile standing about knee deep in the water. This school of little white bass comes buy and starts whacking at my spoon. A bunch of 5-6" whites trying to eat a 3" spoon. I'm skipping it along the top having fun watching the little guys whacking at it. Then one of them literal impales himself on the hook about 10' from me. Well that striper hadn't gone as far as I thought. He sees this little white bass thrashing on my hook and comes roaring in like a freight train. The white bass makes a bolt for cover, but the only cover is me
The white bass goes between my legs and so does the about 7 or 8 lb striper
I had the presence of mind to open the bail, but I also moved my leg so I wouldn't get tangle. That spooked the striper. I pull the white bass in and it was in a catatonic state. Never seen a fish like that. Tossed him back and away the little guy went.