The biggest change to monkchers has been the Enhancement overhaul: the good news is Turbine dropped the feat pre-reqs and beefed up the
AA tree (most of which you can access with just 6 rgr lvls, so you no longer have to be an elf or HE to be 90% AA); the downside is you can only take one tier-5 enhancement from any PrE. In your case, if you really want a centered build using khopeshes (or anything besides short swords), you need Keen Edge + One w/Blade from the
Kensei tree, which would prevent you from taking Slaying Arrow from AA. So right off the bat, you have to decide if melee or ranged DPS is more important to you.
If you're willing to go with rapiers instead of khopeshes, have a look at
Santa's Little Slayer. Right now Elven Grace is the only way to get DEX-to-dmg with longbows. SLS is DEX-based with enough STR to qualify for Overwhelming Crit; however if you're willing to give up OC, you can free up several pts from STR to go into WIS instead.
EDIT: did you come back in time to take advantage of the
8th anniversary event?