Going off what I can remember at the moment instead of digging through the XML, so one or 2 might be dispellable since I haven't looked over that list at all yet...
Crazed - Cannot be removed. But only downside is that it causes Enraged.
Diseased - Cure Disease Spell, Aquae Sucellus, or Pool of Tears
Enervated - Pool of Tears
Enraged - Win in Combat, or Pool of Tears (I think)
Heavy & Light - Cannot "Cure" but it is a mixed blessing, not completely a bad effect.
Vulnerable to Fire - Cannot Cure.
Weak - Cannot Cure
Withered - Pool of Tears.