if they arent getting sentries, they arent doing their job right.
incapacitating bite is great, but not enough imo, without a bkb, the vamp can be nullified completely.
i highly disagree with you about clinks and brood not competing for the same role, brood isnt a good carry and cant mid, and really needs a bkb to last through the ulti.
that means brood is an offlaner that needs both an orchid and bkb befor she can be effective, which takes way too long.
its a hero that needs safelane farm, but her skill tree isnt suited for it.
the only thing brood does well is pushing, and even then, without the items to back her up, shes easilly stopped, put her against a half decent lane, and she falls to pieces.
sure in a pubstomp with a decent mid, on a hero like puck or pudge, brood can be great, but as a reliable choice in higher level games, not so much, I personally havent seen a brood pick up in games ive played in months.
the buffs to web and bite have made her better, but still not good enough imo, i just dont rate her.