It doesn't take long of playing her to see why she is one of the worst champs in the game right now; she has a very punishable laning phase. Irelia's rank 1 CDs on her W and E are pretty long. Bladesurge is not only your farming tool, but also your escape so you have to be really careful with it if a trade is about to happen. W is weird and is on a long CD. Her E has that little delay and takes awhile to come back up. Anyways, this creates a weird feedback loop because since the CDs of your W and E can be easily abused if you misuse them you want to keep using your Q so the enemy's wave is smaller than yours. Then when you do finally get your ult, it's a team fighting ult on an champ that's on an island for half the game that basically acts as an excuse for you to spam Q for a few seconds if it marks enough things.
So basically your kit is based around spamming Q.
I know riot considers her healthy ATM, but I really don't like her current kit nowadays.
For instance I don't know why her E isn't a low damage melee stun on like a 12 second cd. Force her to get into melee range, smack one champ, and they are stunned for .6-1 second. As it is, the E feels slow on her and like it is a bit of a trap. Why do I say her E is a trap? Well it wants you to try and pull off a multi-stun, but your average player doesn't have the timing or mechanics to pull that off. I've found the best use of her E is to stun the sion that is fully charging his swing or wailing on your ADC you isn't kiting.
For me, the current W just feels really weird on her. Why does a melee diver have this weird ranged tanky poke? Her W feels like riot wanted a worse form of windwall in the game but not on the champ that needs windwall nerfed. Her ult basically means you have to take TP and gank bot but that's always a gamble in soloQ because the bot bush isn't warded and your bot lane doesn't know what freezing is. This means the bigger impact surprise ganks while they are overextended are off the table.
I guess I just feel like there's a better possible kit for irelia.