Your cards are digital, you have the ability to retroactively change them if the main mechanic ends up being disappointing
Pop that Thinking Cap on, and lets get to the investigation
BT2-031 U Digimon Lv.6 Vikemon Color Blue Cost 12 DP 12000 Digivolve Cost 1 Blue 4 from Lv.5 Form Mega Attribute Free Type Beastkin Card Text 1 [Effect] [Your Turn] While your opponent has a Digimon with no digivolution cards in play, this Digimon gets +1000 DP and Security Attack +1
That main deck space is also compatible with all Vault X Exo-Tec sideloading deck boxes too, so you can swap decks in and out of this box with ease
Cards that combine Pokemon and trainers into one scene are almost unanimously more valuable than their counterparts in the same set, and the same rings true here
Most of all, the games already-plentiful generic support for Dragon cards via the likes of Super Rejuvenation and Dragon Ravine gave it a natural advantage over its spellcasting rival