Only thing I can think of atm is maybe you aren't 'aggressive' enough. Use aoe smartly, and try to kill as fast as you can. You have to kill them before they kill you. Always keep moving, but not only backwards.
[quote name='shanaeri rynale' timestamp='1373291374' post='2217638']
Are the chests you get RNG? As this part Seems to imply they are..
In the pictures where it shows a large achievement chest, there's text that says a choice of: and then it lists several weapons, so I don't think it's gonna be rng.
If you find ranger fun, stick with it. It is a fairly simple profession to get used to, which has led to a large chunk of its player base being people who don't know what they are doing, but it can be very good in the hands of a smart player.