Gunpla is freedom! No need to wait until you’ve seen the series; just build whatever you think looks good.

If you’re worried about that, though, just build stuff from the Build Fighters, Build Divers or Gundam Breaker sub-lines. Those are just meant to be model kits even within the context of their own series. I especially recommend the HGBF Ez-SR. The base kit is good, but the main attraction is the customization parts that you can use with other kits.