I have played both Savage tiers and all the extremes so far of Dawntrail, and I only had fun while doing Worqor lar dor against Valigarmanda.
The rest felt like I had to study for a fucking test before participating. Valigarmanda I could kinda feel out the fight without knowing too much before hand, it was great. Shame they don't make fights like that the standard, also Mountain fire being rng where Vali is going to be is a cool little reactionary moment of gameplay, I want more of that.