Season 2 has been a season of payoffs. Everything that was referenced to in season 1 has come full circle whether it be the characters or the plot. My favorite part was seeing how each and every character developed from the bland archetypes to well-defined people that you can relate to. Each of them has something driving their actions. The main villain Alus got the most compelling development towards the end. I also liked how the team's bond developed from barely working together to comrades to a real team from season 1 till the end. Their reason for fighting to protect Eldora also had deep meaning. Theplot also did justice to Gunpla's theme of becoming the best you that you can be and Gundam's theme of trying to resisting an oppressive force while trying to reach an understanding with them.
The animation is okay. I don't know why but I find people smiling in Build Divers a bit weird. But the soundtrack does really well to build an impact with every scene.
Overall, I believe that you've got to give this series a try.