I agree with LSK on the Armor issue. While the mechanic isn't totally useless, it's so close to extra toughness so much of the time that it doesn't need to be keyworded. If you want the mechanic, simply type it out by hand.
Purity: As yet, you still haven't shown me a reason to like this...
Consume: You still haven't fixed the wording on this? "Consume [MANA] (When ~ comes into play, remove permanents you control with total mana cost [MANA] or less from the game or sacrifice ~.)" Just copy and paste, and the cards are fixed. The mechanic is okay if you don't use it too often.
Observer: Since your set seems to revolve around RFG-ing, this is fine.
Vigor: I like the way they did it with threshold better: there's a set amount of life for all vigor cards. too much modularity can be bad.
Index: Interesting. You certainly couldn't make too many of these or make them in too wide of a range; tutoring is a powerful ability. But a few (maybe three in each color?) would be okay.
Loreweave: I don't think this needs to be keyworded, as it would be a primarily blue/black mechanic (being milling), and it isn't very interesting besides.
Lorecall: Oh. Well, scratch what I said above. These two mechanics seem very interesting together, although they threaten to be very boring outside of block.
Linger (<THIS> doesn't resolve. Phases and turns end, spells resolve, and players may play cards as though <THIS> weren't on the stack.)
--Most if not all cards with linger have alternate ways to resolve. Some of them have effects that work while they're on the stack. Also, this is in a set where lots of stuff happens on the stack.
X: Quicken ~. (Move <THIS> to the top of the stack.)
Again, in a set where stack mechanics happen a lot, this can be important. And not in block, it evades counterspells. This is a strictly green ability.
Diffusion: I think it'd be cool if it could be circumvented by land searching. Consider that land searchers require land to be played in the deck, so it still makes lands dead in your hand. Also, the reminder text would be more concise.
Trap: Yay gotcha wording! I don't think you even need the <cost> after the word "Trap." Anyhoo, this seems cool, but kind of limited to green (although that's not necessarily a bad thing). Actually, I like it a lot. It'd make a cool Mystic Snake variant.
Singularize: I've seen this in other guises before, I believe. I think it's in RickCorgan's Palouranos (spelling?) block. I like it.
Sanctuary: The glasskite ability certainly doesn't need keywording.
Hazard: Interesting, but I think it's too confusing. Just use flagbearers.
Purity: As yet, you still haven't shown me a reason to like this...
Consume: You still haven't fixed the wording on this? "Consume [MANA] (When ~ comes into play, remove permanents you control with total mana cost [MANA] or less from the game or sacrifice ~.)" Just copy and paste, and the cards are fixed. The mechanic is okay if you don't use it too often.
Observer: Since your set seems to revolve around RFG-ing, this is fine.
Vigor: I like the way they did it with threshold better: there's a set amount of life for all vigor cards. too much modularity can be bad.
Index: Interesting. You certainly couldn't make too many of these or make them in too wide of a range; tutoring is a powerful ability. But a few (maybe three in each color?) would be okay.
Loreweave: I don't think this needs to be keyworded, as it would be a primarily blue/black mechanic (being milling), and it isn't very interesting besides.
Lorecall: Oh. Well, scratch what I said above. These two mechanics seem very interesting together, although they threaten to be very boring outside of block.
Linger (<THIS> doesn't resolve. Phases and turns end, spells resolve, and players may play cards as though <THIS> weren't on the stack.)
--Most if not all cards with linger have alternate ways to resolve. Some of them have effects that work while they're on the stack. Also, this is in a set where lots of stuff happens on the stack.
X: Quicken ~. (Move <THIS> to the top of the stack.)
Again, in a set where stack mechanics happen a lot, this can be important. And not in block, it evades counterspells. This is a strictly green ability.
Seek: Seems fun.
Remind: This seems pretty narrow.
Enforce: This seems much too close to kicker. By the current color wheel, it should be a mono-green mechanic.
Quicken: Interesting, but this also seems too close to kicker. Also, why not make it "If you pay the Quicken cost, this spell doesn't use the stack?"
Gush: Okay, I suppose.
Sticky: Again, much too narrow.
Align: This is more interesting. Essentially, though, you're just making colorless spells, as the original color doesn't matter.
Trap: Yay gotcha wording! I don't think you even need the <cost> after the word "Trap." Anyhoo, this seems cool, but kind of limited to green (although that's not necessarily a bad thing). Actually, I like it a lot. It'd make a cool Mystic Snake variant.