Well, let's see how games have been implementing 'tough' NPCs.
1) You can't attack NPC.
2) You can attack NPC but can't kill him/her. Reload.
3) You can kill NPC. You either die or succeed. The problem lies here. Unless the game has been designed into accommodating the potential death of said NPC, the consequences are going to be pretty shallow. The
'pay a fine and all is well' approach is hilarious.
An alternative is everyone going hostile for the rest of the game, effectively breaking it. But then, why give the option if it just breaks the game (because the game wasn't designed with said option in mind). Otherwise, there's the faction/town hostilities as well. Only said faction/town goes hostile against you for the rest of the game (.... or until you pay the fine -___- ). It works, but it's a rather simplistic consequence. Still, it IS a consequence. BG had the right idea, but terribly executed by having some Flaming Fist dawgs chase after you if you had a horrible reputation. You were essentially playing the same game, except for some occasional people coming out to hunt you. If you're a wanted fugitive, the gameplay should be vastly different. Unfortunately, unless the game caters to it prominently, you essentially WILL be playing the 'same game' with minimal changes. No bounty hunters tracking you down and laying traps and ambushes or false leads, no having to hide your identity and sneak around. Roleplaying a fugitive could be pretty compelling, but when it's such a small part of any particular CRPG, you can't expect the devs to invest such disproportionate resources on it. Which is where paying a fine comes in.