DS9: none (don`t like it)
It's got some great character development and, unique in Trek, a growing continuity/story arc.
ENT: none (haven`t watched it much)
I think it's good. The first two seasons are standard Trek fare, and better if you ignore previous series, but the latter two are very good in my opinion. Some continuity in the third season, and an interesting take on story arcs in the fourth.