Copies of manuscripts don't authenticate the stories within them or make them more valid than Homer. Josephus and Tacitus talked about Christians and what they believed, and were not actual contemporary accounts of Jesus, his miracles or resurrection.
"It is pretty much a consensus among all credible scholars (even very liberals) that Jesus died on the cross"
The evidence is scant and nothing that can really be verified or call 'rock solid'. Appealing to authority by saying, ' even liberal scholars agree', is nonsense. Yes, a man named Jesus that people believed to be their messiah could have died on a cross. This does not verify any Christian doctrine as Christians believe it.
1) Your first point can't be verified. None of it can be verified, from the claim that there were guards to the claim that they couldn't be over powered.
2) That is a bold assumption to say that nobody other than only Christians would regard woman as being worthy enough to be put in a story.
3) This is circular reasoning. You are using the bible to prove the bible.
4) Is their extra biblical evidence of the direct disciples persecution? And is their anyway to verify that they weren't lying, other than assuming they weren't?
This maybe a bit of a jab but if this is the best you can do then you have a whole lot of work ahead of you.