Abra Kadabra mentions the Chronarch. In DC Comics there are two characters known as Chronarch. One is the cruel 64th-century ruler that exiled Abra Kadabra. He was ultimately defeated when Abra Kadabra teamed up with The Flash. The second is a Legion of Super-Heroes character known as Circadia Senius, an insectoid alien and time theorist in the 30th century. His research of time-travel and time-manipulation theory makes him the perfect director (or Chronarch) for the Time Institute.
Cisco's indignation at the name by which Abra Kadabra knows him in the future ("I know he did not just name me") is an in-jokey role reversal, since in previous episodes, it's traditionally been Cisco who has come up with the code names of Team Flash's foes.
This is the first episode to neither credit Tom Cavanagh in the main cast nor have him make an appearance.
Cisco mentions Laurel Lance and Mia Queen when explaining why he made the memory ring, but decides it's Another Story for Another Time.
Abra mentions that sometime down the line, Barry will become obsessed with the future. This refers to the Future Flash. It may have to do with Godspeed, who is a confirmed villain this season and has been sending copycats of himself into the past.