The problem with Roots
If you slow the video down to .25 you can see that I cast my instant root prior to her E. One could argue that her E animation/cast time or w/e is faster than mine and I could agree with that. What I cannot agree with is that she completes her entire fucking backward dash while in my root. Do you understand how frustrating it is for someone to be IMMOBILIZED but still able to complete their mobility. What is the point of Ryze W if it doesn't halt mobility at that instance? There were a number of times in that game where I W Akali but she E's and make it impossible to catch up with her. It's just not fun how many champions are being released mobility that I cannot stop at the moment it is casted. Most of these champions mobility abilities are on a low CD and while Ryze W is on a low CD (it is maxed last so only in the late game) it is evident that these types of mobility are heavily favored. What I suggest is that roots need to have a grounded debuff or something to actually root champions.
rocket jump and 
arcane shift use cast animations... and cast animations can only be stopped by death. as soon as the cast animation stops, the move ability starts... and as the most recent movement ability it overide all other movement abilties.
snare is a short duration and most of that duration took place during the movement animation. and after the root was over she was able to recast to go to you because u got hit by her E's skillshot.
was rooted BEFORE she casted her E she would not have been able to cast it at all until the root ended