Harry has used others as his sounding board, but most are either dead, alienated or Harry has outgrown them in his current need.

I don't think Harry will ever be able to fully trust Lara, that makes her a poor sounding board.

Practically perfect in every way.

That's "Mary Poppins!"  Hmmmm... Now that I think of it she may have a lot in common with Lara Raith.

Missed someone out from your list

Chandler Prime.

Jim mentioned in the Dragoncon Q &A he will be in MM, Drakul sent him to the darkest time-line.

Chandler is an expert on history and time travel, so I expect he will be playing a Basil Exposition role, perhaps not powerful enough himself to get back, but then Harry can bring him back to the Prime timeline, which will have all sorts of ramifications, as I doubt he would see eye to eye with the White Council after experiencing a year in the darkest time-line. Indeed it may be I speculate that Chandler sets up Alt-Harry with Harry Prime to stop him and get home from what may be a decaying time-line, about to be erased by the White God before it falls to the Outsiders imperilling all of reality, a fate Harry has to avoid in the Prime timeline. Harry has connections to multiversal beings aware of their doppelgängers like Mab, and the Mother’s as well as beings like Mr Sunshine who exist across the Multiverse as a single entity. Put the two together and you have an exploration of the multiverse, the Outside and the Prime universes place guarding against the Outsiders as the best hope of winning this cycle.

I think so too, I also think Chandler once back will become Harry's backup.  It makes sense, Murphy is gone, Thomas will be out for a long time and may never return, I don't trust Lara, [she has her own agenda], Michael physically except when archangels takes a risk for him isn't up to it, and yeah, while Sanya and Butters are a great help, the Holy Knights have more to do than playing backup for Harry all of the time, so that leaves Chandler.  He has all the skills, he might be just a bit grateful to Harry for getting him home, and I doubt he will be welcomed or feel comfortable in the White Council or among his fellow Wardens.  Now he may betray Harry at some point, but I don't think so.

No one, Harry takes it from Eb not necessarily upon his death and returns it to Mother Winter earning a huge favour, and removing from the White Council a major magical artefact, which allowed it to act with rank hypocrisy. Harry would see that as a win-win.

This is what I think also.

If it's mostly about engagement, wedding, and faction issues, I think COURTING DISASTER would be perfect. 

You and me both!    I really do not see any good that will come out of a union between Harry and Lara, and that may be what Mab is counting on.

"One day I hope God will forgive me for giving birth to the idea that came next.  Because I never will.  I knew how angry she was.  I knew how afraid she was.  Her child was about to die only inches beyond her reach, and what I did to her was as good as murder".....

Sounds like he made a deliberate decision here.  Hey could have thought of something else, but he chose this.

Or once again it is Harry's conscience beating himself up overly, even though he did all he could at the time to save both her and their daughter.   They were losing the fight, Maggie was about to die, so what did Harry do? Told Susan the truth about Martin.  He may call that murder, but it wasn't, Susan still had a choice whether or not to tear Martin's throat out, she knew it would complete her change.  Heck it may have happened anyway the moment Maggie's throat was cut, and there wouldn't have been anyone or anything to stop her turning.

 Susan's final words..
"Help me please, save her please.."  Um, at that point killing the Red King wasn't going to happen, in spite of all his efforts, their daughter's throat was about to be cut.... Once that happened, Harry was dead, Maggie was dead, Eb was dead, and Susan would be a vamp.. Another way to save their daughter?  I don't think so, Holy Knights, powerful Fae, Odin, the Black Staff and others of the Grey Council fighting to stop it from happening, and they were still losing, Maggie's throat was still about to be cut by the Red King.. Also hate to get technical here, but when Harry did cut Susan's throat, she was no longer Susan, she was the youngest Red Court Vamp.  So he didn't murder Susan, he murdered the youngest Red Court Vamp, if she was still Susan the spell reversal wouldn't have worked.   So like we see in Christmas Eve., Harry beats himself up with woulda, shoulda, coulda, when in truth he did the best he could and it wasn't enough.  Even though it was the only way to save little Maggie, and her mother was no longer a human at the point that he killed her, still hurts and will always hurt, so he beats himself up.. But did he really have another option?  No, is the answer.

Yep, it was around when they showed Bill's and Yoshimo's bodies.  Harry was intentionally spared, and Carlos was next on the chopping bloc

Mavra says a lot of things, that doesn't mean it will go her way.   It still was a draw, and as Listens to Wind says, that's a win..

Harry survived because he was for Drakul.  Mavra could have killed Dresden in an instant.  He was helpless.  He wouldn't have faired any better if Mavra wanted to kill him like the others.

Huh?  I don't remember Harry being "for" Drakul..  Harry fared better because when he sneezed huge iron anvils fell out of the sky..  Then again as Listens to Wind said, if you fight these kinds of creatures to a draw, it is a win..