Or alternatively, Mark isn't anti-Marcionite because maybe he wrote before Marcion was born.
I don't see anything on the page that Mark favors any particular would-be orthodoxy. The baptism fits with any number of christologies, from delusional through the Prince of Heaven. Herod's theory of a John the Baptist revenant is depicted as neither unique nor solecist. Maybe the point of the performance is to present some of the diversity of approaches to the puzzle of Jesus.
The poorly kept messianic secret can be fully explained by the secular need to control crowds in the story universe. Apart from Jesus being wary about being crowded, Josephus (or if you prefer pseudo-Josephus) tells us that crowd-drawing is what got John killed. Yes, Jesus is on a suicide mission, but his objective is Jerusalem: to die there, not to be killed en route.
He commands demons to shut up.
But not former demoniacs; he even commissions one of those to spread the word in the Decapolis. And the demons? Jesus is accused, in a crowd, of being in league with them after Mark has established that a conspiracy has been hatched to destroy him. How helpful for the defense that demons explicitly worship Jesus.
He tells people not to spread the word about his healing of the sick.
Some, not others. Many of the healings are public events anyway. (The lover of irony will appreciate that Jesus publicly cures Bar Timaeus's blindness apparently shutting him up about
sedition, speaking of things that could get someone killed.)
He teaches the crowd in riddles, so that they can’t understand him.
So that
some can't understand him. On the page, Jesus's teaching, not just his free eats and free healthcare policies, draws crowds. Odd, then, if nobody understands what he's saying. Oh wait, some of the headline teaching isn't in parables. The divorce thing is plain enough: Moses made it up. Regardless, apart from his disciples, there's nothing on the page about anybody else actually being left in the dark by figurative expression. The Syrophoenician woman, for instance, not only gets his riddle, but turns it back on him. By the time he gets to Jerusalem, apparently everybody gets the subtle-as-a-brick "Tenants" parable.
Moreover, his own disciples fail to comprehend his teaching or his intentions.
And nearly 2000 years later, specialists with earned doctorates are still arguing over what Jesus was on about with the seven Jewish-style baskets of left-overs
versus twelve less distinctive baskets.
The MS hypothesis fits the data only loosely. It is also a solution to a problem that Wrede had, but that Mark evidently did not. Mark's Jesus preferred to acknowledge his claim to the messiahship at a time of his own choosing, as suited the mission profile as he understood it. Apparently Wrede felt that Jesus should have courted death from the outset in Galilee, where Antipas already had one notch on his belt, is depicted as being aware both of Jesus and his disciples, and "Herodians," presumably allies of Antipas, were conspiring to destroy Jesus.