I think my biggest problem with the discussion from mythicist perspectives, here and elsewhere, is the inability or unwillingness to discuss at the level of very minute details and specifics. If one paints with a broad brush, saying that Christians are all incredibly biased and completely untrustworthy (whereas atheists supposedly have no ax to grind and are unbiased), it might just seem plausible to some who've had an experience of particular kinds of dogmatic Christian faith. If someone looks at the details and the history, then what one finds is that whenever atheists (scholars and laypeople) are citing classic scholarship about the Bible as part of their arguments against fundamentalist Christians, they are mostly citing Liberal Protestant scholars, who were of course the ones who pioneered the methods of historical criticism of the Bible in the mainstream academy. If one uses William Lane Craig as an example one gets one impression, and understandably so, given the fact that he isn't even mainly New Testament, teaches at an Evangelical school, and so on. If one asks about Dale Allison, one is still dealing with a Christian, and this time a New Testament scholar, but in this case only the most dishonest individual - or someone who hasn't read what Allison has published on the subject - could pretend that he is simply someone who follows his biases and imposes them on the evidence.
One of the things that makes mythicism seem particularly implausible to me is precisely the claim that Christians just think there was a historical Jesus because they are biased in favor of his existence. The historical Jesus, a figure who (among other things) was mistaken about the imminent arrival of the kingdom of God that he predicted, who fostered hopes that he would restore the dynasty of David to the throne but was executed by the Romans, is not much of a comfort to the majority of Christians. Mythicists imagine Christians saying "Well, he was mistaken and a first-century figure that we can scarcely relate to, but I take great comfort in the fact that he existed." That just doesn't strike me as plausible.
I think my biggest problem with the discussion from mythicist perspectives, here and elsewhere, is the inability or unwillingness to discuss at the level of very minute details and specifics. If one paints with a broad brush, saying that Christians are all incredibly biased and completely untrustworthy (whereas atheists supposedly have no ax to grind and are unbiased), it might just seem plausible to some who've had an experience of particular kinds of dogmatic Christian faith. If someone looks at the details and the history, then what one finds is that whenever atheists (scholars and laypeople) are citing classic scholarship about the Bible as part of their arguments against fundamentalist Christians, they are mostly citing Liberal Protestant scholars, who were of course the ones who pioneered the methods of historical criticism of the Bible in the mainstream academy. If one uses William Lane Craig as an example one gets one impression, and understandably so, given the fact that he isn't even mainly New Testament, teaches at an Evangelical school, and so on. If one asks about Dale Allison, one is still dealing with a Christian, and this time a New Testament scholar, but in this case only the most dishonest individual - or someone who hasn't read what Allison has published on the subject - could pretend that he is simply someone who follows his biases and imposes them on the evidence.
One of the things that makes mythicism seem particularly implausible to me is precisely the claim that Christians just think there was a historical Jesus because they are biased in favor of his existence. The historical Jesus, a figure who (among other things) was mistaken about the imminent arrival of the kingdom of God that he predicted, who fostered hopes that he would restore the dynasty of David to the throne but was executed by the Romans, is not much of a comfort to the majority of Christians. Mythicists imagine Christians saying "Well, he was mistaken and a first-century figure that we can scarcely relate to, but I take great comfort in the fact that he existed." That just doesn't strike me as plausible.