Do the new boosts still apply to other areas of the game as they do now? So "Army boost in Guild Battlegrounds" will be used for the continent map, Exploration Sites, Quests, etc., and "Army boost in the Guild Expedition" will apply to PvP Arena and neighborhood defense.
Also, what happens if you drop out of Diamond during a Championship and then get back in the season after next. Even at 1000LP, one bad season (6th or lower) can drop you down to Platinum. Do your VP total and ranking reset? Related question, what if you're in Platinum when a Championship starts and then move back to Diamond the next season? Are you just SOL for 3 months? Are you not allowed to move up to Diamond? Can you move back up if you drop out? Not a concern for the powerhouses, but for others it might be.
I guess that wasn't really feedback, so ... As a member of a small guild (<10 members) this probably isn't going to be great for us and being on a map with more than 1 powerhouse guild will still be 11 days of frustration. At least it will be a little different, for a while. I don't think you can actually 'rebalance' GBG until you do something about the matchmaking. Remove the LP cap, change it to factor in Guild size, or use long term VP totals, something to make it more equitable.