How I (someone who wasn’t playing Magic during the time of blocks) would reintroduce blocks to the game:

Personally, being told of a time of blocks while not being there to play them makes them seem like both a blessing and a curse. I would love to see blocks in the game, but only 3 sets each year would also hinder the game experience in my opinion.

So here’s my solution: 2 “block” storylines each year, each with 3 sets. One of those storylines can be from the world of Magic itself in classic storied fashion, but the other one being a set of related Universes Beyond Sets. To introduce a story element to these beyond sets, I think it would be good to have a subplot of Jace traveling the multiverse and accidentally creating wormholes/portals/whatever that create routes between the Magic world and others. This would also mean 5-10 cards could be set aside for cards showing either Magic characters alongside the UB characters (eg. Momo and Fblthp, Smallest Friends), or cards about Jace in these new worlds.