So, I am just thinking out loud...
If the game lags cuz of all the RNG calculations on server for item sets and skills etc. Because of load of requests per popular skill/item-set coming to server every second. And other such things.
Then maybe they should just limit the "dice rolls" to, just 100 or 10, on-server dice rolls per second. And give the result of the latest one to the latest request. Instead of rolling 1000s of dice rolls for all the 1000s of requests?
Or delegate some of the calculation jobs to the client.
With a surprise, random and unexpected checks from server. Just to see if the client is being hacked or not. Resulting in bans if found guilty lol.
I don't know.
I haven't seen the numbers or the code.