I was playing vs a computer.
1) When I bounce a face down morph to their hand (retraction helix in this case) I should get to see which card it is.
They should also be revealed whenever they go to any hidden zone, so spells that put it on top of the library, or if it's face down on the stack counterspells that put it back in their hand or into the library.
FIXED2) When I cast a spell with delve (
Dig Through Time), I should only be allowed to exile up to the number of cards equal to the colorless mana I could spend on the spell. You can't overpay to exile more cards if you want to. This is actually a change to the magic rules, the current implementation was correct before Tarkir.
https://github.com/magefree/mage/issues/571