A few issues then:
1) To whom then is Paul/the wuthor of Hebrews, addressing when warning of falling away? It seems clear to me that he is addressing feloow believers, warning them not to fall away, and not those whom have already chosen to be outside of God's saving grace.
2) Taking in context, 2 Peter 2:20-21 says "For if, after they have escaped the defilements of the world by the knowledge of the Lord and Savior Jesus Christ, they are again entangled in them and are overcome, the last state has become worse for them than the first. For it would be better for them not to have known the way of righteousness, than having known it, to turn away from the holy commandment handed on to them (emphasis mine)."
It here again, seems clear to me Peter is dicussing those whom have truly known Christ and were accepting of his sacrifice for them, but subsequently denied him by submitting to the ways of the world. So if anything, this seems to affirm Craig's case.
3) John 10:28 need not be problematic, for indeed those who are truly in Christ will not fall away; no powers can possibly interupt or revoke this gift of God upon one making the conscious choice to accept it.
4) If we have been given free will, why can we not always return to our Father's house, whereupon he will most certainly rejoice in our return (Prodigal Son)? Are we only given one chance at repentance, given on this logic our mere sinning continually even under the care of salvation, makes God "look foolish?" Should he not also have the power to direct stop or prevent us from doing so? Why doesn't he then?
5) Why think choosing salvation over death is by work? If God has given us free will, I see no issue here nor any compromise of God's sovereignty. After all, God asks us as well commands us to do a great many things such to affect change, such as pray, repent, and do missionary work- why have us do these things if God already has selected before creation those whom will be saved? Is our life then, just an elaborate farce?