Illidian definitely did get better but he is not generally good like nozdormu (who now also is a bit less good then before). He needs specific situations so you need to be bit lucky to get the cards.
He is ok-ish with pirates but he is very good for synergys with the macaw early in the game.
Macaw on the left end,macaw on the right end and then a spawn of nzoth in 2nd spot is very strong in the midgame (and if you only have 1 macaw then macaw left and spawn right).
It allows you to easily level and go for the macaw goldrin baron composition relativly safely but you need a macaw and a spawn (and you can not roll often in the early turns so you kinda need to get them in the shop).
The other card that works in early game with macaw is bomb and to a lesser extend selfless hero but spawn is best by far and always attacking first with illidian is a huge advantage. Macaw is the best card you can buy on t3 with ilidian,maybe even more important then bomb or spawn since there is 2 of those and other deathrattles,while far less good then spawn are still ok-ish.
Macaw can work with mechs (bomb) but deathrattle spawns are a bit clunky for the parrot,its basicly all about spawn (and goldrin later when you can slowly switch your comp to full beasts).
Then there is the lizard strat,hooktusk is king of this strat so if hooktusk is in the game you can kinda forget about the lizards unless maybe you find 2 in your first shop though even then it will be dificult to get the lizards before hooktusk and there is only so many.
Flurgle for murlocs,similar to patches for pirates are both pretty ok for forcing a tribe. You need a murloc (or pirate) early on else you will fall behind fast and then you need lots of luck to catch up.
Both these heroes can stay at tier 1 slightly longer to get the tribe going so you dont have to level on t2.
For example with flurgle if you start with tidehunter and you find a rockpool on t2 i like buying the rockpool and roll,to see if there is another murloc for next turn.
The meta is fast and volatile,it is very unforgiving if you make mistakes.
If you level to early or dont optimize board and minions every fight then you can take a lot of damage (20 is not uncommon).
On the other hand you also can not afford to stay at low tier improving marginally to try stay alive either because you will fall behind quickly.
Only saurolisk can do that since they improve a lot every turn,saurolisk is very resilient against this volatile meta.
Saurolisk is weaker in a slower meta where the other players dont knock eachoter out fast,then more players have the change to get to an endgame comp that can beat saurolisk but in current volatile meta saurolisk naturally floats to the top and then stays there very often.
Demons are very weak,nowhere to be seen other then as a semi tier 1 strat with darryl,pyramid and sometimes hooktusk. Mechs are also weak and dragons do feel kinda slow. You need get kalcgos early else you wont be able to build up.
Beasts are good and have many variations but the ultimate endgame is with the parrot which is easy to get.
Then there is the cannon. Personally i dont like the card at all and i rarely buy it because it somehow distracts me from my plan but that is probably is a mistake. The cannon seems solid and good when you have 4 minions or more. Somewhat similar to spawn and bomb but without any scaling potential.
Its strong up to the point where your minions dont insta die when they attack which is usually at the border of tier 3/tier 4.
Pirates are difficult to get going,they dont have that much synergy with non tribal cards and you also can not easily transition with them i feel. Like you can late transition to beasts with a mama bear or a goldrin and a baron. You can go murlocs with a bran and a bargurgle.
Pirates dont really have those options to get into them later on in the game,in that aspect they are kinda similar to the big demon meta we had before if you dont have them early with a good start then its near impossible though some of the individual pirate cards can still be ok for a temporary spot.