The problem is that Trials illuminates the meta in a more visible setting. Thorn was always strong, people'd bitch about it in IB. TLW was always a rumble god, Hawkmoon was Hawkmoon. Pulses were the best and thus used everywhere. Sunbreaker was actually less scary in Trials, but they were still nearly impossible to reliably kill in 3s. If anything I would say keep Trials because it shows what's imbalanced, just like the Nightfalls can do the same for PvE (warsat).