Ok, here are my thoughts on these.
First "Predict" keyword, I like it. Allowing to have some control on your next draw is kind of nice, almost insuring you that you'll have something you should be able to play, or something you need or in worse case scenario avoid something you don't want by not having a 9 drop draw in turn 2. It also seems to have a very lost "cost" as the cards shown here with it seems to be "Costed" pretty normally.
Ancient Preparation: It looks pretty good, first you get to predict which should have a decent chance of something useful for your next draw, and the little tempo loss is offset by having a 1 mana 2/2 in two turns. The real strength in my opinion is getting a Prediction early which can benefit other cards in a significant manner.
Clockling: Token from Ancient Preparation, so good enough for what it is.
Aspiring Chronomancer: Vanilla stats for a 2 mana card, early Prediction which is probably why you want it to enable some of the other cards. Should see play in Predict decks but that's it.
Xenotype Researchers: A little understated but not much, effect is great though. 3/3 on 3 cards that's a lot of added stats. Play this in an overwhelm deck to get some dangerous value out of them. Hit cards like Zed, Silverwing Vanguard, Navori Highwayman, Evershade Stalker...or any cards that make a copy of a card to get more value from the buff. It has a lot of potential I think.
Khahiri The Student: This will most likely always come out as a 4/4 for 3 mana which is pretty good, only going to be played in Predict decks though.
Khahiri The Returned: Low base stats but has the potential to grow, he could come up pretty big in late games if you get to predict him more than once, or if he gets buffed by a Xenotype Researcher as I assume the copy will have the buffs. Again only going to see play in Predict decks.
Preservarium: I think this is decent, draw 2 for 2 mana, just a few turns apart.
Promising Future: I don't think it's very good right now with the Landmark with Countdown that we've seen. Getting a 2nd Clocking from Ancient Preparation is not worth 4 mana, neither is drawing an extra card. The Sun Disc would in theory summon 2 of all your Ascendants which may be ok, but most likely simply be "win more" so not sure the card is any good right now.
All in all, most of these seems good but limited to Predict decks only, hopefully there will be a few viable version.