Illaoi is pretty bad; a kit improvement is needed
the state of Illaoi as a low visibility champion with mediocre to poor performance across pretty much every elo, as a supposed "noob stomp" champion, deserves some addressing beyond a mere numbers buff
my proposition to improving Illaoi's lacking kit is adding onto her ult; since she is already heavily reliant on R to be threatening this is not adding any undue change to how you approach her, but makes her better able to actually fulfill her function as a zone-heavy nesting champion
Give Illaoi a "soft wall" on a far outer circle on her ultimate, big enough that she can't trap people in it but small enough that her ultimate can actually create somewhat of an "oh shit" moment like Illaoi's ult is supposed to, rather than being almost laughably easy to negate even when you have misplayed massively simply by walking backwards.
this soft wall should be... lets say at a distance of 700 from Illaoi, maybe further and a circle about 2 Teemos thick. It doesn't block movement but you are slowed by 15% passing through it and you can't dash out (but you can dash in.) You aren't CC'd if you try to dash out; the dash simply ends at the perimeter of the wall.
This does not add any CC immediately next to Illaoi so the counterplay around fighting in her tentacles does not disappear, but Illaoi can now better define an area as her threat zone and offer more meaningful team contributions to her pick, as well as making it more of a risk to engage on her recklessly.
A very reasonable suggestion.