I experienced some lag too, but just reconnecting things gets better (sometimes not but most of the time yes).

One time happened that a guy in map left and immediately lag stopped......don't know if related but timing was perfect.

Hex staff proc enhance ping up. But I would say only when you have 8-10 mobs that are "burning really well". Usually happen when you have 2/3 hex in map.

Just my 1 cent