This is the most important bit:
"Starting with the first Grand Arena Championship, we are going to slightly reduce the weighting of pure GP in the matchmaking system for GA, in favor of a larger set of variables intended to make players feel less like Grand Arena is punishing players for going broad. If you are working on newer or lower-powered squads, the matchmaking system will be much less likely to count those efforts towards matching you with an ideal opponent, and you will be less likely to be paired up with a player who a) looks just like you GP-wise, but b) has instead spent all of their efforts optimizing a smaller handful of squads. (Those players will still be rewarded for their strategy in Grand Arena, but they’ll be matched up against someone who looks more like them.)"
As far as I understand it if the algo aligns with the stated intention (regardless of your division) you'll now get matched with peeps that are similarly lean/broad as your roster. Assume there's no such thing as purely lean or purely broad. An almost purely lean roster player can keep that way and can get matched with others that are also almost purely lean...or can bump their gp with fluff a bit, become -less lean- and can get matched with similarly -less lean- players.
And developing your roster regardless of usability or your aims with it is rewarded through divisions. Let's not forget what's pure fluff for me at 4M+ GP range (i.e. g8-g9 stuffz) is pretty usable and has to be used in matches along 2M gp. It's a player concern what to consider fluff almost at all times, an ideal matchmaking algo needs to be blind to that, only finesse the similarity of rosters overall to be fair(-er- than it was).
We know nothing about how small or large GP intervals division system will bring along yet.
