i think that you're underestimating the other's DEX.
i think that most people have above 200 DEX. while you have 300 atm, the accuracy rate of the opponent on your archer is surely not low.
if you have checked
this discussion thread concerning DEX you can find out that, when you are 300 DEX
--> the player on 200 DEX will have 63% accuracy on your archer
( there is a limit of 95%, so capped it )
--> the player on 150 DEX will have 50% accuracy on your archer
and i didn't have counted in buffs which can help the another person, like
-> concentration
-> agility
-> sharp shooter
so, it's still risky to think that you cannot being hit regularly