In terms of sheer numbers for the main portal deck, you are correct...this would add to the variety without diluting the set too much. Where this could become a problem is the potential difference in card backs/frames (whether or not you could tell a set apart by the difference in the printing tone of its card backs), though I think they are supposed to be identical with sets published after the Apprentice Edition. Someone from StoneBlade would be able to answer this question a littler better. In my humble opinion, the Apprentice Edition could expand the deck without adding in major-crazy effects, so I'd say go for it.
Thanks! It is rather cheap so I'll risk the card backs and see