Microadjustment balance changes are based on a formula that takes into account the current bucket information, which is why they don't happen until at least a few days after bucket adjustments. I believe we sent over the public bucket information a few days ago to our community team but it's possible it didn't get to the right folks. I'll doublecheck Monday.

For 15.4, we're going to try doing an arena patch without buckets and have all cards be part of one giant pool. This is similar to how the early days of arena worked. Theoretically, buckets made individual arena decisions a little more interesting and put more weight behind how a card works in the deck you are drafting vs its power level in a vacuum. While I think there is some truth to this, I don't think it's been a well received change overall. For players new or inexperienced with Hearthstone, the idea of having 'obvious' choices is a win. For hardcore players, if the change to buckets is not a clear upside (which has been most of the feedback we've received here) then it's probably just not worth doing. One positive part of not doing buckets is that the micro-adjustment patches should happen faster in the future because there does not need to be a preliminary bucket adjustment patch to set the stage.

Welcome back 9+ flamestrike.

Arena in the original format just had way less cards which was mostly the reason individuals showed up more often. In the bucket system, cards that appear the most often show up around 1.5 times per draft. In a system with no buckets, that number is reduced to around 0.9. (Source)

I knew this would be a divided topic, but it's good to get it out in the open so it doesn't come as a huge surprise later. There are a bunch of benefits to having no buckets. We don't have to do a rebucket patch, so the initial balance patch should come out a week after the patch rather than 2+ weeks. Decks should feel more different from one another because there are no small buckets that made some groupings of cards appear more often than they would otherwise. As another result of getting rid of small buckets, the cards that appear the most often should be seen around 0.9-1 times on average, which is quite a bit less often than the cards that appear most in the current system (1.5ish). There, of course, is also some downside. This is true with every design decision. We already have buckets completed for 15.4 if we wanted to use them. It's not a question of doing the work, it's done. It's just a question of which system feels better. After spending so much time with the bucket system, my personal opinion is that buckets make drafting a little more interesting, but sacrifice the gameplay experience by making decks feel more similar than they would otherwise. Which is more important is subjective, but I think it's healthy to try different things. (Source)

Just for clarification, We are not going back to picks with same rarity ,are we ? I personally like this move it is more encouraging to casual players like me .

No picks by rarity. And great, I hope you enjoy the swap :o. (Source)