I just looked at all my domains with the most keywords:
#1) - 41 keywords
#2) - 35 keywords
#3) - 31 keywords
These 3 domains are TWO WORDS. Notice that almost all the domains you posted from MediaPlow are two words...
Conclusion: Brandable domains with 2 root words usually have more keywords. MUB/suffix domains only have one root word so less keywords.
Cheers!
Most of your two word domains have 10-15 keywords. I didn't see any that had 41. Your portfolio isn't that large so it was easy to go through. Having two words in the domain then your keywords should definitely go up but it's not always the case. The keywords aren't even the same when one of the words is the same in two different domains. I used these two domains from your portfolio as an example.
KeepCart has the keywords cart, e-commerce, keep, Online Marketing, sales, shopper, shopping cart, technology, wish lists
StackCart has the keywords, buying, cart, commerce, internet, manufacturing, online, organized, retail, shipping, stack, versatile
As you can see even with the word Cart in both domains the keywords related to the word Cart are totally different which means they are manually inputed and that is why some portfolio holders have more keywords and others don't. Maybe the BB team chooses names that they think have a better chance of selling and manually input more keywords to give a good domain a better chance at selling. I don't know if that's the case but it seems this way. Why waste time manually inputing 30 or 40 keywords on names that they think have no chance of selling.
Another example is one in someone else's portfolio Cartzy. Cart is the only word in this domain but the keywords are Boutiques, bright, carts, commerce, fun, internet, malls, memorable, online, playful, purchases, retailers, sales, shopping, shops, stores, transactions. This domain only has one keyword not two keywords but has more and different keywords then the other Cart domains.
It's obvious that the keywords are manually inputed by someone on the BrandBucket team so it's safe to say that some portfolio holders can have 40 keywords on a similar domain while someone else only has 10.
I can sit here all day and analyze domains but the bottom line is some sellers are able to have many more keywords then others.