I have a Ranger / Rogue and am concidering adding a level of Monk to boost his AC with the wisdom bonus. I am not very familiar with the monk abilities at all and wonder if this will be worth it or not.

Currentl runs Icy Rainments, Bracers AC 7 etc... and uses Rapiers.

Stats: with items etc
STR: 21
Dex: 28
Con: 13
Int: 16
Wis: 16 could boost 4 more with item
CHA:18

I dont want to move away from his rapier build, but am not sure if i add the monk class if using the weapons will dirupt any advantages I get.

Looking for input and appreciate any comments.