There’s not a whole lot else to see and do on the Nexus right now, but what little there is should still be covered. First thing you should notice when wandering about is that there are a few Angaran onboard now. Diplomacy moves fast in times of crisis. Speak to some Angara Diplomats near the door that leads to the Tempest to learn that the leader of their delegation wishes to speak with you.
Fair enough. Make your way to the Cultural Center where you’ll find Isa de Navar - the Angaran ambassador. It seems that there’s a bit of a dispute concerning the Angarans and Nexus protocol, and given their past experiences with aliens, it’s understandable. Respond how you will, especially on the matter of earning their trust. While this event doesn’t really advance any quests, you can head into the Cultural Center and talk to another Angara named Andraknor, who suggests a cultural exchange of a different, more martial variety. This starts the quest "Task: Earn your Badge", which takes place on Voeld.
Task - Path of a Hero (Part 3)
Finally, before you run off to another planet in search of more significant, lucrative quests, find Keri T’Vessa, who wants to continue her interview with you. Chat with her and tell her what you will about the Angara, and the possible colonization of Aya by the Initiative. Afterwards, if you’ve been flirty she’ll attempt to advance your personal relationship… you know, just as soon as you’re done with your professional engagement.