If the resources come from thin air, what is the point of a bounty from a revenge? The guy doesn't lose any if much loot.
And if it's cheap to do, 5,000 resources of your choosing, everyone's going to use it. The cool down is good, but this won't stop the trolls. If I had this feature, I would use it to troll rather than to exact revenge as I'd at least keep those around so I can do something that would hurt them directly.
The price definitely needs to have a higher minimum so you have to be really angry to put someone on a bounty. 100k minimum to put a bounty on someone.
The biggest problem I see with this is that now people will farm bounties.
I've seen a bounty type system in similar mobile app games, so it could work but I think this may be too drastic of an update for Clash. It's interesting, I wouldn't bounty anyone but I sure would keep my eye on the bounty list!
This could still be exploited if the system places a bounty on a global list based on trophies. I could find someone on my revenge list that is exactly at my clanmates range but super easy to beat. I tell him "Hey I'm about to list this guy in 3....2....1" boom, pops up on the bounty list, he takes it and gets an easy bounty.

