An interesting mechanic that might prove to not be worth it from a fun gameplay perspective is giving enemies the option to surrender or flee if they feal a fight is hopeless (just blew up all theirs friends with a meteor shower for example) ultimately though I think it would be frustrating to lose out on XP/ loot from enemies who fled.
Which is completely feasible if you give XP for "defeating" enemies (kill, flee, surrender, change sides) instead of just death.
That is also one of the things often requested, and re-requested, and re-re-requested, continously in the Neverwinter Online Foundry community -- being able to grant non-combat experience and rewards.
In the "DM Tools" I would love to see being able to simply "grant" bonus experience or other boons for "creative" solutions, or interesting role-playing.
