Hearthstone just kicked a year's worth of cards out of the game for the second time. I had stopped playing for a bit, fed up with seeing the same old thing. The game now, as it was at the start of last year, is amazing. There's huge variety, everyone is trying new things, there's a bunch of viable stuff. The best decks will rise to the top, but they're new for a good while. It's given me a lot of optimism for netrunner post red sands. It's also resurrected my belief that ffg should chop harder so the card pool is easily manageable. Having a legacy format is probably good, but 'standard' should probably only have 3-5 cycles.
That way you can design with purpose to move the focus of the game around. I really hope rotation works in ANR like it does in Hearthstone. I'm excited again.