I would have to agree that the Resurrection of Jesus is probably the best Christianity has to offer in the way of argument for the religion's valdity. And don't mistake me...the arguments do come across in apologetic rhetoric as both sound (historically) and attractive.
I haven't undertaken a full-scale study of the Resurrection, but I have recognized a number of problems, especially methodological and presuppositional barriers in dialogue about the historicity of the Resurrection. Assessing it tends to lead into debates about the philosophical soundness of taking seriously claims about the supernatural in historical investigation and several other things relevant to the evidence we have--mainly the NT--such as the reliability of this evidence. How early are the gospels? Who wrote them? Are there parallels in other religions that would help make sense of it? etc.
Uncontested eyewitness testimony would be strong evidence in favor of the Resurrection. However, most scholars (and definitely not just skeptical scholars) believe the gospels are not eyewitness documents for many reasons that themselves are debated; scholars argue over the genre of the gospels; Christian scholars amongst themselves argue for theological reasons whether or not the Resurrection should be propounded as historical, and so on and so on. So it's difficult to argue the Resurrection because one is constantly diverging on assumed 'facts' and it's hard to ever get to the point.
I do think there is a misguided tendency for apologists to confuse the stories themselves with 'facts' as if they sometimes don't draw clear lines between the stories as they are written and how we as moderns use them as interests of history. They ask for alternative explanations that coincide with 'all' the evidence. When one is suggested, they dismiss it by pointing out certain narrative details in the stories themselves. All the documented 'evidence' we have is found in stories where the Resurrection is the denouement itself. The stories are designed so that they culminate with the Resurrection. Of course no alternative explanation is going to comport with stories specifically written around and about the Resurrection's centrality! The stories weren't written to allow for 'alternative explanations'.
There are other arguments, which I regard as largely sophistic, that apologists use to argue for the historicity of the Resurrection. These often include appeals to the 'Jewish backround' of the nature of resurrection. These arguments restrict novelty as a factor. Not every theological construct has to have predetermined, laid out, cut-and-dry antecedents to it.
For instance, they might argue that Jews (which constituted the original followers of Jesus) would not have engineered a theology where the messiah would die, rise from the dead, and then ascend to heaven. Why? Because we can't find any writings from contemporary Jewish thought where a dying and rising messiah was expected. Jewish ideas about resurrection were universal and would transpire in the final eschatological institution of the kingdom of God...not within history with a single individual, namely Jesus. Although there are instances of singular revivifications in the epics of the Hebrew bible (e.g., 1Kings xvii.17-23), none of these, they claim, serve as analogues because they are mere 'resuscitations' (where the raised would die again)...not 'resurrections' (never to die again in strict accord with Jewish apocalypticism/eschatology). Therefore the 'best' explanation is that the Resurrection probably happened!
But seriously...come now, how could we possibly know this? Are we to take seriously the implicit suggestions that Jews made such category distinctions as we use? Would the superficial difference between 'resuscitation' and 'resurrection' have mattered? Did it even exist? Can the apologists demonstrate that it did? Likewise with 'history' and 'eschatology'. Just for a moment, imagine that the Resurrection is false, that it never happened and that Jesus' followers were coping with his death and needed to find a way to explain it. Are apologists really going to suggest that while these Jewish peasants sat around and thought about it, some one, let's say Peter, concluded that Jesus rose from the dead to glory and that he could make sense of it through tales of the Jewish scriptures, and that another, let's say Matthew, discounted this theological solution with a solid: 'Nah, Peter. I don't think so. That wouldn't make sense because, remember, "resurrections" don't happen in history. They're reserved for the "eschatological" age'?! It's difficult to take these kinds of arguments seriously (and also, so much for the early church predicating their belief in the Resurrection event on the scriptures--see Paul and the speeches in Acts, for example). This line of argument also ignores the strong apocalyptic atmosphere of this period in Jewish history. Jews did think they were living at 'the end' (just read any of the various apocalyptic texts from this period, especially the sectarian works of the Qumran sect for extrabiblical examples and Daniel and Revelation for biblical examples), and obviously a specific group centered around Jesus believed that, as the messiah, he was leading the way in the final 'eschatological' resurrection as the 'firstfruits' from the dead (cf. 1Corinthians xv.23).
At most from a historical perspective, we should be agnostic about the historicity of the Resurrection of Jesus. For myself, I reject it because not only do I disbelieve in God, but in my studies of the Hebrew bible, for example, I find it to be the work of primitive people filled with error of all types, and the NT bases its theology on these error-ridden (and in many instances, repugnant) documents. Jesus himself, if we can trust that the gospels have reliably transmitted his words, affirmed these writings as God's very inerrant word (e.g., Matthew iv.4; John x.35--cf. Mark xii.26 where he places importance even on the tenses of scripture). They reinterpret them, they contradict them, and the NT also contradicts itself...including in narrative pertaining to the Resurrection. In all this, I do not see some divine program. I see men, legend, and myth.
Thanks,
E.L.B.