i run around with 70 ping usually, i notice a big difference when i get 200 ping (issue from our side)
reaction is slower, when i cast a spell it takes about half a second/second before my char starts casting time
and I notice this because usually its almost instant, click 1 cast time of 1 begins
so when ur hugging a tree and its all done on reaction speed, that slight delay will make sure
your opponent is safe behind the tree again.
Still I find RO still playable at 200 ping, i start getting trouble and being frustrated when i get 500-1k
although at that time im prolly losing connection
(this game actually isnt all that ping sensitive.. just look at LoL..
whenever Im upset about ping I play or remember what LoL does with the same shift in ping

)
And when the server is located in US other people will have bad ping so there is no perfect solution
Im sure you know it could be far worse, be happy with what you got