Lately, when players from distant places play each other (not all of them, but most), they experience terrible lag. I've tested this with players from nearby. Canada to US seems very choppy. Also, I've had two games crash in the last 12 hours after repeated disconnects and reloads by several players. These disconnects come in swarms.
Something is going on within your links between the different server nodes. I'd put some packet analysis on it and look for a bad fiber hub or bad server board somewhere.