Besides her kit having nearly nothing to do with being a floaty blade master? Mostly she suffers from bloat. She was created when melee characters where significantly weaker to ranged, so they overstuffed her kit so she could compete with them. Lets go over her kit shall we?
passive: 10% to 40% cc reduction that stacks♦ with tenacity.
q: a targeted dash that refreshes♦ cooldown on kill.
w: auto's restore health and a active that makes her autos deal true♦ damage and doubles♦ the health restore
e: A 60%♦ slow or a stun♦ when she's lower % health than her target.
r: 4 line nukes that restore health on hit.
As it stands she's just got an answer for everything. If just half the mechanics were removed from 1 or 2 abilities then Irelia would still have a competent kit. You'd have to rebalance numbers of course but she'd definitely still be viable.
Personally, I want Irelia to get a visual and gameplay update because they are wasting the potential of the flying blade master fantasy. Her current(modified) kit could go to her brother as a "new" champ.
♦
http://paulgoodenough.com/principal/wp-content/uploads/2014/03/image11.jpg