One dilemma this card presents: Do you exile a card that you're likely to gain this shuffle, or do you speculatively exile a card that you'll gain in a future shuffle?
I guess the way I use Duplicate, I often let it sit on the mat through shuffles, to wait for a better card. Camel Train seems even better for this purpose, as Camel Train will not skip shuffles. So we may see a lot of exiling-for-later with Camel Train. Looking forward to it.
Something I'd like to see in future bonus previews, are attacks, or otherwise interactive cards/landscapes.