Opening the select language dialog, it appears tiny compared to the rest of the interface.

I don't see an actual Bug, here. On my device it's about the same size as the small dialogues in Options -> Advanced -> Game.

It's much smaller than the oversized general "Options" menu you come in from, but those don't have any actual controls (like dropdown lists).

Ray chose to use the smallest standard interface size, and I do NOT agree with that from a design standpoint, but the entire UI is in the middle of being re-designed and changed to different User Experience parameters.

So, as far as I'm aware, there is not a Bug here. It is functioning as intended.