I sometimes think Bill is exactly what many college-level/college educated people need to read. When it comes to apologetics, I tend to be far more pragmatic than dogmatic.
For instance, in the philosophy or religion I will always prefer Swinburne, Plantinga, or even MacIntyre (I know he's in Ethics, but much of what he says can easily cross over into religion) over Bill. At the same time, I can't hand Plantinga's "God and Other Minds" to a sophomore in college who is doubting his faith or questioning Christianity; I can, however, give him "A Reasonable Faith" and guide him through it.
I still think we're missing too many Continental philosophers of Religion who are Christians (I purposefully exclude Gianni Vattimo, John Caputo, Peter Rollins, or others). I'm not necessarily referring to those in the neo-Marxist or post-Marxist tradition, but simply someone who can write in an existential format and is easy for the public to understand. The philosophy of religion is almost exclusively analytical (if one seeks to be orthodox that is), and I think that's a shame since Christianity is an existential religion.
Anyway, I digress. I think Bill's works are fantastic for college students. He doesn't offer a lot of original thoughts and he's not a philosophic innovator (though he tries to be). But that's not a bad thing. Rather, he's a synthesizer and takes from different philosophies to paint a bigger picture. This means that his explanations will be less technical and a bit more sloppy, which is fine and affords him the chance to not clean it up (in certain situations) because it would force him to get bogged down in the details. I myself am a synthesizer when it comes to philosophy (though I do have two theories that I want to develop at some point that would be innovative, even though they're ancient), so I'm certainly not putting him down by labeling him a synthesizer. Few people can be innovators like Plantinga (who's concept of warrant was almost entirely new) or MacIntyre (who's virtue ethics helped found a revolution, though in all fairness Philippa Foot really worked on it prior to MacIntyre).
The three issues I have with Bill's philosophy are as follows:
1) His attitude and demeanor when debating atheists, especially hostile ones
2) His over-reliance on the Kalaam argument, to the exclusion of other cosmological arguments (likewise, I just don't think the Kalaam is that strong as it has to consistently be unpacked)
3) He's too Aristotelean and doesn't allow for mystery as a legitimate answer, leading to some questionable beliefs concerning God and time. In fairness, he would say that he does allow for mystery, but it really doesn't come across in his writings or debates