This is surprising, you are actually the first guy who has mentioned that its actually good that we lost our knockback on rocketpunch.
Melee based root on a stationary caster is not actually something i call a good ability. The same dev team made warhammer online and they had a class in that game called the magus, a ranged spellcaster with a melee based root and a aoe knockback....it was considered a free kill for just about anyone with a hint of skills in that game aswell.
But if this junk works for you, then im stunned...and ofc happy for you. Still stunned though
I generally use to immobilize them and then los behind a pillar and heal, it works wonders on any melee class and sometimes even ranged. I sometimes miss the knock back but I found this is be an overall positive change for myself.