The thing is a lot of the errata and changes only really effect non causal play, where the players should know the errata. In casual play does it really matter if your arcane ring doesn't affect your moonglow amulet that wasn't cast from a battle forge?
I personally think that while this is a nice idea to replace everything, for those of us who have got 6+ core sets, and multiples of each expansion then it is too much to pay to replace a few hundred cards. Pick up the new core sets as they come out as I am sure that Arena isn't the last reprint.
On the note of core Tome 3 to reprint multiples of staple exapansion cards? I think this is an awesome idea, this is a way for newer players to buy in at a reduced cost. It could even be the same the LG series and include a few new things to keep the Vets buying it as well.
