The first season of 'Kaguya-sama: Love Is War' were basically short skits about a game of chicken which wasn't something I was a huge fan of.
The second season offers a bit more variety. A lot of people were expecting the same style of humor but I feel the show is maturing, something I can really appreciate. There is a more serious tone this season, a bit more focus on life outside of the student council.
Both Shirogane and Kaguya have been humanized a bit more, Chika doesn't get shoved down your throat as much as the first season, Ishigami gets the development he deserves and we're introduced to a new member of the student council called Miko Iino. Miko Iino is used in the same manner as Ishigami was used in the first season, so I'm expecting a lot more character development for her in the third season.
Some huge improvements compared to the first season and, as mentioned, actually looking forward to the third season.