Soo I finnaly found the missing link of ice weapons and... apparently what I thought was the tier 2 version was actually the tier 3 :(. The average damage of t3 elemental damages are:

Fire: 9.5

Magic: 8

Lightning: 7.5

Ice: 5.5

Ice is almost half that of fire :( and usually have very low charges. Is there a reason behind this?

Ice weapons deal damage over time. you ever notice the little cold puff come up on the target a few seconds after your hit. Ice may acctually be the best for that reason... also if your fighting ice elementals with ice weapons then of course its going to do a lot less, even less than a normal weapon because they have immunity against ice.