I'd prefer never having existed to death at the moment. This might change later if I gain meaningful accomplishments, but I'm not sure how likely that is.

Sorry, how did he stand to benefit from telling Harry about the plaque?

Does Harry even count as an enemy in MoR? Seems like he'd need the blood of someone on Dumbledore's side, and if he's just as arrogant and greedy as he was in cannon, then he'd go for the blood of Dumbledore himself.

Excellent.

Meta 1: It would be nice if reviews rated the material out of 5 or 10.

Right now, reviewers are starting with things like "Absolutely fantastic." and "Extremely, extremely, recommended", which, while are a nice indicator of high-value materials, is less efficient and more fuzzy than a rating on a standard scale. This would also motivate more people with medium value materials to come forward.

Meta 2: I think this would be much better suited to a wiki piece than a post/set of comments. Ideally it'd be in something like a collaborative evernote, but I don't know of a free evernote clone.

Sorting into top-level categories seems poorly suited for indexing the material. For example, your post on The Blueprint, from your review, sounds like those trying to optimize social skill just as much as those trying to optimize romance. Tags, or a list at the top of a wiki, linking to anchors, would do better.

I'm not sure what you mean by "runs an app for all users", Are you writing a separate app that you want the hangout to automatically open on entry? Doesn't it make more sense to do this the other way around?

We're not comparing Dumbledore in his thirties to Snape in his thirties, but Snape in his thirties to AD at "64". If we assume that he's been using his time turner since age 11, like HP (though based on his backstory, it seems he got a large intelligence boost at 10, so that might be where he started), he's effectively over 77 when he fought Grindelwald, giving Snape upwards of 4 decades (longer than he has lived thus far) to reach Grindelwald-defeating levels of power. In addition, we know that Snape has good reasons to hide how powerful he is (especially in MoR) and has a substantial amount of muggle knowledge. These all indicate that he's in the same league as Dumbledore, but benefits from not broadcasting the fact. This would also explain the way he was described in MoR.

And...

...the book said that a successful Legilimens was extremely rare, rarer than a perfect Occlumens, because almost no one had enough mental discipline.

Mental discipline?

Harry had collected stories about a man who routinely lost his temper in class and blew up at young children.

...but this same man, when Harry had spoken of the Dark Lord still being alive, had responded instantly and perfectly - reacting in precisely the way that someone completely ignorant would react.

The man stalked about Hogwarts with the air of an assassin, radiating danger...

...which was exactly not what a real assassin should do. Real assassins should look like meek little accountants until they killed you.

He was the Head of House for proud and aristocratic Slytherin, and he wore a robe with spotted stains from bits of potions and ingredients, which two minutes of magic could have removed.

Harry noticed that he was confused.

And his threat estimate of the Head of House Slytherin shot up astronomically.

While Snape is in his early thirties, it seems unlikely the extra three decades would make all that much of a difference.

Keep in mind, in HPMoR, it's heavily implied that AD's artificially aged because he's been overusing time-turners, possibly since his Hogwarts days.

No, HP could go back in time and call himself Tom Riddle. Especially if he was becoming one of those "Dark Wizards who change names like you and I change clothes"

Predictions: Tom Riddle is Hat-n-Cloak (95%). Tom Riddle is female (35%). Tom Riddle was Voldemort, but the title was taken over by Qmort who is not TR (20%). The feeling of doom between HP and Qmort is because of time travel (95%). Qmort is an older HP, sent back in time with memories removed (30%).

Since Rowling follows around HP and not HG, we don't actually know how HG thinks. Since JKR wrote the story, she can use preknowledge to make HG arbitrarily smart, and since she doesn't have too large of an impact on what actually happens, she can do this without needing to account for how smart HG is; even if she were to devise some genius plan to beat voldy, she'd have to act through HP, who could easily and stupidly reject her plan offscreen. That is, I'm arguing that even if you kept making HG arbitrarily smart (but not arbitrarily powerful or prophecy-choosen), you could easily keep everything else the same by making HP or some other characters arbitrarily stupid, possibly offscreen.

EDIT: Oops, I edited the previous comment to leave out the phrase "since HG acts rationally" a few seconds after I posted it, since that's not really what I meant, but you seem to have beat me to the response.