21.5 The word for "Child" here is paidia, which means "child" not "friend" as the NIV has it.
21.5 Jesus asks a "meh" question which expects a "no" answer. (ou questions expect a yes answer. How can one remember this? Alphabet. m-n; o-y)
21.7 The word for "cast" is "ball-oo" which is used for both the nets and for Peter.
21.9 Jesus is cooking over "anthrakia" which means "coals" (ie anthracite coal). This is the same place Peter earlier denied Jesus.
21.11 The net is not torn (schiz-oo). Interesting that John concludes with the net not being schismed; in Mark's Gospel, the Gospel almost ends with the curtain being torn! Different metaphors, for sure, but something about the nature of Jesus in both is nicely caught with this subtle difference.
21.12-19 I refuse to comment on the various types of love that Peter and Jesus use. I don't think that John makes much of them; he uses them interchangably. If anything, the ambiguity of "philo" and "agape" points toward the intimate (and therefore mutuable and vulnerable) and transcendent (unconditional and permenant) love of Jesus toward and with his disciples.