As houndoom is reprinted, i'm guessing houndour will be also. Also notice how Houndoom is number 10 in the set which means that as it begins with H i recon lots of holos will be in the set. Also as hitmonlee was in the blister pack picture as a cover for the promo I recon the whole hitmon line will be reprinted with hitmonchan and lee from undaunted and hitmontop and tyrouge from HGSS.
Theres a posibiliity that all the shiny legends could have non shiny counter parts in the set as holos and rare which would answer why houndoom is number 10 (deoxys, entei, ho-oh, groudon,dialga)
On the more random note I hope they reprint some eeveelutions just for pure awesomeness.
The lugia from the scan shows it in a mini set like the arceus cards from Platinum: Arceus. This means there might be primes and legends in the set or some other super rare cards such as Lv.x's or the single card legends similar to the ones shown in the japanese black and white sets.
And of course all of the lost link cards should be in there and i see no reason why lost world shouldn't be printed as it can always be banned if needed.