Terry's little brother Matt is playing with two model rocket ships, one of which is a model of baby Kal-El's Kryptonian ship featured in Superman the Animated Series.
Deducing from Terry's quip, Bruce told him about Alfred Pennyworth.
Terminal is voiced by Michael Rosenbaum, the voice of several other characters on Batman Beyond and went on to voice Flash on Justice League and Justice League Unlimited.
Interestingly, in the feature film Batman Beyond: Return of the Joker, Rosenbaum voices another Joker, Ghoul, whose real name is given as "Stewart Carter Winthrop III".
In a possible nod to Batman: The Animated Series (1992), Max said she needed a hobby and investigating Batman "beats macrame". In Joker's Favor (1992), when Joker muses that he needs a new hobby, Harley suggests macrame.