We are indeed left with a ton of questions.
"Jesus" is sandwiched between John and James, two characters of some historical consistency, to which Christian sources relate him contradictorily: John is presented either as an immediate "precursor" (but he obviously had an ongoing line of non-Christian disciples, which would be quite strange if he had really pointed to Jesus as his "successor"), or a close relative (Luke), or a more remote figure (Jesus can be presented as the "resurrected John," cf. also "since the days of John the Baptist"); James is either a "brother" (literal, as the Gospels imply? spiritual, as the title "brothers of the Lord," parallel to the "apostles" or the "Twelve," suggests?) or a disciple (the striking parallel between the inner circle of disciples in the Gospels being "Peter, James and John" and "Cephas, James and John" in Galatians; Acts 12 has the "James of the Twelve" killed by Herod just before James of Jerusalem pops up from nowhere).
Very little of what is said about James in non-NT documents (Josephus, Hegesippus) suggests a relationship to Jesus. One can imagine Jesus and James as members of the same (Nazorean?) movement, but James hardly appears as a "disciple of Jesus". Moreover James is a kind of aristocratic priestly figure in Jerusalem rather than a Galilean popular prophet-rabbi.
If there is room for a historical Jesus from what is not purely literary fabrication from OT material in the Gospels, the hypothesis of a Galilean nationalist seems among the most plausible; but then the connection with John and James becomes dubious. And there are many otherwise known contemporary historical figures (e.g. Judas the Galilean) which may have provided the model for the construction.
Anyway, the "earthly Jesus" that really matters to Christian faith is the one who walked on the sea: the god-man that can be built from the Gospels, rather the historical person(s) that may have stood behind them.