My only hesitation (other than not having looked at it in years) would be that, as you might expect from Bruce, it is quite conservative, but that sounds like what your questioner is looking for, so that might be a plus.

Here! I just found it on my shelf…. My recollection that it is, like all of Bruce’s work, very thorough and thoughtful. Indeed a quick look at the Table of Contents and the Index shows that he deals with all the major issues. In fact, two appendices have lectures he gave in the 70’s, one on the Secret Gospel of Mark. The latter chapters look very strong (and my notes seem to show I appreciated it 15 years ago when I read it ) and deal with the issues that your questioner is concerned.