BO3 limited rewards are too paltry and BO1's hand smoother ruins real Magic
Basically, EV for BO1 is far better as I'm sure most know, but BO1 is frustrating with the hand smoother allowing for high variance and take-the-best-card multi-splashing multiple colors. BO1's EV for going .500 is -500 gems (receiving 1000 while paying 1500) while BO3 is expected to be 1.5 wins (or -800 gems) with top end payouts being the same as a trophy in BO1. Improve BO3 payouts, or at least have less variance between the wins. A 66% win rate in BO3 receives a -500 gem payout while the same WR in BO1 achieves above +100 gem payout. If you want people who get frustrated by BO1 variance and hand smoothing nonsense to still play arena, you need to improve BO3 payouts.