My comments below are strictly based on pre-Covid conditions - who knows what Club Level will be like upon it's return.
AKL- some of the best cast members I have ever had the pleasure of meeting. Every single cast member was so friendly and accommodating. We checked in around 11 am and our room wasn't ready until around 4 pm. The entire time in the lounge (it was pretty empty), they were so attentive, refilling our drinks without asking, asking if we needed or wanted anything, and just chatting with us while we waiting. From the moment we stepped off the Magical Express, it was an amazing experience. The food was great! The only downsides are that there are no spectacular views from the actual club level lounge (aside from the view of the lobby!), and our room was not on the same floor as the lounge.
Poly - amazing views from the club level lounge, the two story glass window with views of the castle and fireworks was amazing! Again, our room was not on the same floor as the lounge, but the buildings only have three floors so it was just a quick flight of stairs. I found the adult beverage selection to be one of my favorites out of all the club levels!
Boardwalk - honestly, I really dislike the theming of the lounge, but the cast members here were amazing! I remember that this lounge, more so than the others, was always full of dirty dishes left on tables.
Wilderness Lodge - best food ever! Definitely my favorite food out of all of the club levels. The beer on tap is awesome, not sure if it will return when club level reopens. One thing to note, several of the club level rooms are right above a service area, and when I was there, there were always service trucks that were very loud, starting VERY early in the morning. There are rooms on the other side of the hallway, but just something to note.
Contemporary - amazing views (obviously!). I recall this club level lounge feeling very stuffy and "corporate." Personally, I found nothing special in terms of food or atmosphere.