I remember the article posted here when David Wade opted to return to Kerry's staff in 2009 when he was in the position of having been greatly respected for the work done on the 2008 election. It is also good that Lowenstein is going too.
As to not being able to get the "deal" HRC got, I suspect that it and a few articles speaking of how hard an act HRC will be to follow - including one that said that Kerry would likely be the "caretaker" of the Hillary Clinton/Obama foreign policy - are all part of the effort to deify Clinton. I do think it is clear that the State Department people respect, admire and like her, but I think like all things Clinton, her accomplishments have been hyped. (I also remember that in 2009, there were many long time Kerry people - most notably David Thorne - who got some of the coolest ambassadorships - with articles at the time saying that Clinton preferred they go to diplomatic professionals, ignoring the "Friends of Bill" that got them in the 1990s.)
Although this could be configured as being in the shadow of Kennedy, while that was real, I suspect that this is more US media pushed. It also might give him the lack of attention and space he needs to carefully work on things as he did for the last 4 years.
I also STILL remember the article on Kharzi a few months after Kerry persuaded him to do what Obama wanted, that there was a prominent article that spoke of Clinton - from DC - speaking to Kharzi using the very words that Kerry spoke of using (his own acceptance of the election). This may have been the clearest form of praise for what Kerry did - ascribing it to HRC. I do think that if Kerry is fortunate enough to have success anywhere, there will be many describing how the roots of whatever he accomplishes were set by HRC. (Shades of the Republicans claiming GWB deserved part of the credit for getting OBL) I just hope that there will be things that happen that the Republicans - and the Clintons - want to claim. That will mean Kerry has done well.