I'm startlingly close to being maxed out on BDR, wow. I mean, theoretically, I can get 11 more, actually, which... sounds like a lot, but I'm at 28, and most of the remaining possible improvements are Fate and/or time locked, or in one case, from Seeking, so.
Like... I'll be getting one soon from Fruits of the Zee, One is ambition or Whitsun (and probably effectively Fate locked), I can reasonably get one more on weapon from Fruits (other improvements are ambition, Feast Fate, or seeking), one more from a Fate locked transport (or ambition item), I can get a ship, and then in theory I could get 2 or 3 from a spouse, but the 2 are Feast Fate locked and the 3 is... very expensive Fate locked, I believe.
So, like... I'll hopefully get another 2 from Fruits of the Zee, if I went for a yacht, I could get another 2, and then... everything is pretty much out of reach for now.
Also very nice for the new stats this year, too. My first Mithridacy item, Red Science, Player of Chess...
Also: turns out Fruits of the Zee is really good for BDR improvements. I'll have gotten essentially a +4 from all the Fruits items by the end, and several are BiS.