WowAce

What is the enhancement in mind? How should it look and feel?

An option that, if toggled, will ignore every debuff matching selected type of debuff (e.g. Magic, Curse, Poison, etc.), with an exception list similar to the existing ignore list.  User can enter the name of the specific debuff(s) they're looking to track for dispel, instead of entering every other debuff that exists into the ignore list.

Note that you can already disable debuffs by type by unchecking the types you don't want to cure in the 'cure options'

Yes, and that's a great feature. But even if you only selected Magic debuffs, in order to only track Polymorph, you would have to enter every magic debuff except Polymorph into the ignore list. This would be an easier and faster way to do that.

I mean I searched for a complete list of magic debuffs, so I could enter them all except maybe 4 or 5 that come to mind, but I couldn't find one.

This feature and other requests could be solved by letting users define and add custom affliction types. The Affliction Type would be a list maintained by the individual or by the community. For example it would also mean Paladins, Hunters and others could add an Afflication type that covered Slows/Snares that their Hand of Freedom/Masters Call can "cure". Another example would be Mages/Priests/Paladins that can "cure" Knockback Effects by using Slow Fall/Levitate/Bubble.

The Lists would not have to be maintained by Decursive. Depending on if you could create a single or multiple List Standards for the various types of Lists that Decursive currently supports, Exclusion Lists and Priority Lists it could become quite a feature of the addon letting the community trade tips on what configurations they use and why their setup works best for them.

This is already partly planned in the following milestone:

http://www.wowace.com/addons/decursive/milestones/

Every one has their own enhancement in their mind and it can vary from each other. I am excited to know about the exceptional list rather than the regular one. I have been looking for college papers to buy for my projects. And visiting here gave me a chance to update those curse positions.