I saw in the release notes for U14 that the Trip and Improved Trip rate for mobs had been looked at and dialed back significantly. Excellent job on both recognizing the problem and in fixing it.
Now I think it's time to look at mob's Evade. Once I started running quests in the mid-teens levels and up, the incidence of mobs- and I'm talking just regular 'trash' mobs, not mini-bosses or bosses here- Evade my Air Sorc's various lightning spells (bolt, ball and chain) a disproportionately high amount of time. It's gotten to the point where I only cast my high damage spells once, see mob after mob Evade, and then switch to Electric Loop and Force Missiles. At least I know they WILL hit and do SOME damage, thus not totally wasting my spell points.
I'd ask that the Evade rate be looked into and, if found to be as high as I think it is, dialed back at least somewhat. Keep in mind that the mobs get a Reflex save for half damage in all cases anyway, so they have a built-in way to minimize damage.