Sorry, but with current state of Boolberry (not even in top 100 marketcap - no development since months) and the few differences with XMR or XDN, it doesn't seem to be useful to put Boolberry in the comparison
Unlinkable transaction upgrade to CryptoNote and blockchain bloat reduction are probably the two biggest upgrades to any CryptoNote currency so far. XMR has probably done a bunch of stuff too but I can't think of a specific thing off the top of my head that could be more important than those two upgrades. XMR devs plan to do their own versions of these upgrades down the line, but they have a lot on their plate so I wouldn't expect them anytime soon.
CryptoZoidberg is still around. He's done a lot of work and it's a bit silly that you would dismiss that and have the balls to put Ducknote above BBR in relevance.
I agree with Este Nuno. BBR should be on the list over XDN. Boolberry, while low in marketcap at the moment is part of the SuperNET collection of coins with big plans/uses in the future on that platform. Darknote was trading at 12 satoshis just 2 months ago before it had a 600% increase. It's more of a traders coin than a working currency practicing anonymity. Give them cred, they chose a good platform but it's been a joke