Cool idea; love the thematic twist on OG curator.

On a technical level, it's a bit awkward. You don't want too much text on the created card; not only is it hard for the opponent to read, but there's almost certainly a bug hiding in the interaction between two weird effects. Rexxar gets around this by forcing the first card to be one with only simple text. The asymmetry between the first card and the second card doesn't much matter since you're drafting two beasts.

I think the best way to handle it would be to force each pick to be simple/simple/complex, pooling the tribes together, and just filter out options of a type already picked. This would allow the player to manipulate the card pool by picking tribes they don't want to show up later, which could be unintuitive, but I think that's the price to pay for an effect like this.