How is it badly designed? All you have is that its scripted? Considering that a vast majority of everything in this game is scripted, that isn't a real reason to single out Titan EX specifically. If you have an issue overall with "scripted" fights, then you should make a thread more general on scripted fights and talk about it there. Titan EX is a vast improvement upon Titan HM, and is overall one of the more fun fights we have. Do I like fully scripted fights? Not at all actually, but that doesn't make Titan EX a bad fight or *not fun*.
I think SE has a lot of room to improve in the area of "scripted fights", but that is a general beef I have with their end game and I don't mind Titan EX at all.