As a rogue, I wish to have conditions for Hunger For Blood so that it only shows if a bleed debuff is present on my target.

Unfortunately, WoW doesn't give an API to show if a target is effected by a bleed effect.
UnitDebuff can detect Magic, Disease, Poison and Curses. But not bleeds, stuns, slow, root. fears, etc. The only way to do something like that is compile a custom list of spells and effects, and keep that in the addon and check if those specific debuffs are present. Something I've not wanted to do/maintain thus far.

That sucks.
I don't think there will be much maintenance after first version on such a list, but I have never developed an addon so I wouldn't know.
Thank you for your comment and love the addon.