Since Time is missing two skills right now, I'm wondering if I could suggest some kind of 'precognition' skill.
It could be called fortunetelling, forecast or divination, to avoid giving 'precognition' multiple meanings.
The basic idea is that your opponent has to give you some hint about the deck he is going to use (some time before the duel, eg. when you are arranging the time to duel, so that you have enough time to design your deck). The hint should be useful enough to help, but not big enough to allow you to completely predict the deck.
For example, if it was a Tier 1 skill, the hint could be the number of elements used (eg. mono/duo/rainbow), or the number of cards used.
If it was a Tier 2 skill, the hint could be 'a name of a non-pillar non-pendulum card, that the deck uses at least 3 copies of', or maybe something like the average cost of the cards used.
I don't really know, maybe someone can come up with better suggestions that would follow the theme.
Of course, if it's too complicated or the idea needs to be scrapped for other reasons, I'm fine with it. I simply wonder if some skill of this kind would be seen as limiting to the opponent (since he has to avoid predictable decks) or as an opportunity (he makes a big deck, trying to trick you into thinking that it's a stall... then it proves to be a phat rush, or for example he announces that the deck will be rainbow, but in fact uses cards like animate weapon/upped sundial/photon/spark and only 2 or even only 1 type of quanta).
It could even be added as a one use item available to buy in Time towns and cities, that would force your next opponent to give you a hint.
Also, it seems that 'some Time ago, in a galaxy far far away' Blizzard already designed a number of skills for Time Elementals:
http://eu.blizzard.com/diablo3/characters/archivist.xml
http://www.diablowiki.net/Archivist
Namely:
* Book Vision: Which makes every book on screen glow a golden color, the use of this is not mentioned.
* Lorenado: A Tornado of books ripple out from the Archivist, ripping apart any one foolish enough to stand in his way.
* Quest Bolt: Sends out a golden exclamation mark that travels straight until it hits something. When an enemy is hit, they are "Frozen", for a Quest Mark appears above they're heads, indicating they have a quest for the player.
* Shush: The Archivist lets out a "Shush", after which, all enemies within 30 feet are ripped to shreds.
Not bad. It could work.
But one issue is that it would either..
A) Limit deckbuilding 
of the other player because he has to tell details of his deck before he has even had to design it
B) Give the player who uses it, very little to use the information to his advantage
I guess we could do it so that the deck info is released 5-10 minutes before the duel. This way the player has some to tweak his deck. It's not much, but it's still better than limiting the deckbuilding of the opponent.
One option would be this: let the player ask one yes or no question before the battle. For example I could ask "Do you have any Novas in your deck?", and my opponent would be forced to reply truthfully yes or no. I could be pretty cool. 
So I think the best name would be Foresight, or Forecast. As for the 'yes-no' question thing, the problem is that questions can be very vague, and also people might misunderstand themselves. For example:
-Is your deck fast? / Is your deck a stall/control deck? etc. are hard to answer due to blurry definitions of 'fast', 'stall' etc.
-Is your deck a bolter deck? (what should the person answer if his deck has 3 bolts for example?)
-Is your deck cute? (lol, no comment xD)
-Does your deck contain permanents? (Did he mean non-weapon non-shield permanents? Or are weapons and shields also considered permanents? Even if there are 'global definitions' for these, people might still misunderstand each other due to the colloquialy used definitions that are different, or even due to M:tG confusion
-Does your deck contain creature control? (Is PU considered creature control? How about procrastination? How about plate armor + gravity shield?)
So I guess there needs to be a list of allowed questions, or some other solution to make it more precise. Although I do think it would be one of the funnier skills, causing many fun situations
As for the issue of how much time before the battle should the answer be known, I'd stay with the 'when they are scheduling the duel'. That's because the answering player only partially limits his deckbuilding when he answers the question. He probably has some general idea for his deck at the time, and he can adjust details after answering the question, as long as as the answer is still true. On the other hand, the asking person might have to completely rebuild his deck depending on the answer, and if the answer was given 5 minutes before the duel, the asking person would simply have to design two decks beforehand, optimized for each answer
, and use one of them depending on the answer.
Of course, the latter is also an option, simply forcing the Time player to do some more deckbuilding
(let him pay for choosing so irritating skillz)
As for
, I'd say they are an element of controlled changes (in contrast to
- the element of random changes), and also a good element to give some wizardry/sorcery powers (making their spells more powerful or something), so I'd say we should move the Convert skill from
to
(It's a very powerful Tier 1 skill in my opinion, certainly one of my first off-element picks), and maybe split it into:
Tier 1 - Convert I - 1AP: Convert up to 3 creatures/pillars to any non-rare creatures/pillars of your choosing.
Tier 2 - Convert II - 1AP: Convert up to 3 spells or permanents to any non-rare spells/permanents of your choosing.
And their Tier 3 skill could be something related to global spells... maybe "consume a relic - cast any Tier 1 or Tier 2 spell"
As for
, I'd change their skill:
Ambush - First duel gets restarted until you win the coin toss.
Into:
Ambush - If opponent wins his first coin toss, he skips his first turn. (ie. ends turn without playing anything)
The original skill could be irritating if either the players are constantly desyncing or simply RNG hates them. The changed version is in fact very similar, although the consequence is that on average it gives the air player 1 card advantage, but hinders some deck-out strategies a little.
