The conflicts you mention are real, but can be compartmentalized within DOJ (at least that’s valid legal reasoning).
Sessions appears to be correct on the law. However, I believe DOJ is derelict in it’s prosecutorial discretion.
Conflicts in which a SP are expected by tradition and demanded by the expired law are conflicts associated with the POTUS.
I completely disagree. Conflicts of interest are part of the book of law and the acceptable list of them is a mile long, so these easily qualify. Not to mention Session's DoJ is using unequal standards to analyze criminal behavior when judged in the context of Trump v. Clinton. Only an outside untainted SP could be trusted at this point, and even finding one of those among the D.C. swamp creatures would be difficult, look how Sessions turned out for example.