I know the convention up North East uses core set for first rounds ect. That maybe too restrictive for players who like other mages tho.
I think this may be a reference to the WBC tournament held in Sevens Springs Resort, PA. This summer the WBC Arena tournament did expand the format to allow all Arena mages and cards, but continued to exclude Academy cards. We also dropped Apprentice mode from the demos and tournament rounds in an effort to attract more experienced players.
I need to provide a post-event report with details but here are the highlights. We had 11 players participate in the two day event with a customized Straywood Beastmaster (Chris Byrd) winning the event for his third year in a row. New players to the game were allowed to select any standard book of the 14 possible mages to use for the 4-round tournament.
The Academy cards have been excluded on the basis that interactions between Academy (with still evolving rules) and Arena rules have not been fully documented (or systematically tested). In addition, the card effects and interactions between the two product lines are more likely to involve questions that would interrupt games during the timed events.
RE: Variety
I don't see a fixed card pool as the end of variety. However, it does change the focus of variety to exploring different strategies and tactics within the range of decisions a player has to make both before and during a match. The Arena only format provides players a choice of 14 different mages with unique training across 10 different schools and 14 different combinations of mage abilities. It also provides 482 unique spell cards distributed over these 10 schools. Plenty of variety by these numbers.
I prefer to see the glass half full of water rather than half empty. Adding Academy cards to the tournament glass feels like mixing oil with water just to fill up the glass. It does add a new taste to the overall drink, but I prefer the water only. Other tastes will vary ...