Also, do yourself a favor, and focus str over dex. You can put 4 into each, each lvl so they will both get pretty high. Str adds perm. damage to each attack and the dmg added doesnt decrease when you lvl. AKA 400 str at 30 adds the same dmg as 400 str at 50. However, dex does decrease. 400 dex at 30 may cap your crit percent, but at 50 you need 900 to get the same crit percent.
Just an added note here....damage bonuse returns which come from Str increase based on your level. So at L30 you may 0.8123 damage per point of str, at 50 you would get something like 0.9150. These are bard numbers from :
http://www.vgbards.com/forums/index.php?topic=1821.msg19097#msg19097 so they aren't accurate for monks, but I've found use to be pretty close (Bards < Ranger < Monk < Rogue I believe in regards to str returns).
Crit Returns from Dex do diminish based on level just as Fuj says, but the ranged damage bonus from Dex works just like str does in that it increases based on your level.
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