I'm not too sure about 1 and 2, but as far as 3 goes, since you're going to have a bounty on all players, It kinda already does keep track of it, although I'm not sure if TD would be able to show it. On your players tab, double click each player, and within it, there's a section for bounties you can look at. Alternatively, under status, you can see how many hits the player has.
If I recall correctly for #2, showing the prizes will only show the label by default, and I'm not too sure if/how to show the recipient of the prize.