I'm a huge fan of Love Live, but the previous seasons of superstar had failed to really grasp me. While season 1 started promising, it got a little side tracked between plot points, and season 2 was an all around mess. I didn't go into this season with high expectations.
However, I'm very happy that those expectation were wrong, because somehow they turned it around and delivered one of my favourite seasons in all of Love Live. Superstar season 3 finds it's own story and really reminds me why I fell in love with the franchise to begin with.
The first episode shows us one of the more interesting setups of a new idol story: Kanon, the protagonist, leaves her old group and joins their old rival Wien. I truly love how this is brought; Kanons motivations make sense from her point of view, she has always been driven by competition and it would feel weird to come back after saying goodbyes. Yet, it is portrayed very clearly in the reactions of others and the sound design that this is misguided in the grand scheme of things. This narrative choice also gives us the chance to give some more screen time to our new characters, Tomari and Wien. Both are excellent additions, have their own motivations for the way they approach being an idol, and them having ties to Liella helps in making sense of them ultimately joining together as one group. However, I will say that is the main point I think was reached too quickly, and a little contrived. It made some of the drama around the two rivalling groups feel unnecessary, because their conflict has no winner and loser in the end.
After this, the show puts the focus on what I think should have been Superstars identity from the get go: succession. The third years are leaving, and are shown pursuing their own future endeavours, while combining this with making one last great effort to win Love Live one more time. If we're real, this victory was never in any doubt, given that Sunny Passion graduated and no new rival is built up at all. However, the focus of succession gives the second years full spotlight to develop themselves, and Shiki, Natsumi, to a lesser extent Mei but to a fantastic extent Kinako all show growth as characters and take on new roles in and outside of the group. This is brought to conclusion with an absolute home run of a final episode, that celebrates the starting five

Spoiler, click to view

I almost screamed when they went onto the rooftop for Hajimari Wa Kimi No Sora, their debut single

and shows that Liella is ready to keep on moving on. It makes sense they are the first back to back winners of Love Live, because they managed to reinvent themselves between the years. However, I would like to see them celebrate a win on stage for once, I don't know why Sunrise insists on having the victory as a timeskip.
The music is good, as you can expect. The ED is a bop that as always has different characters sing it each episode, making it sound fresh every time. Bubble Rise is beautiful, Dazzling Game is something new and fits into the story really well.
Seriously, go watch Love Live Superstar. This season is worth it.