One thing that really bothers me in this game is that the positioning of the two players after a grapple finishes is unpredictable. Sometimes the players end up close enough that a grapple can be immediately followed by another grapple (either counter or followup). Sometimes they're far away enough that a counter or followup grapple will miss. This is not due to using different grapples. When I play gunner, I love doing the double grapple. Mortar grab, then skill grab. Sometimes it works, sometimes it doesn't. Same grapples every time. I've seen it work against assassins, and I've seen it fail against assassins, so it's not different because of the classes involved. It is not due to the other person moving out of the way in time. I've had plenty of cases where I've tried to counter-grapple an assassin, only to somehow miss while she moves TOWARD me slashing with her sword. Please try to fix the post-grapple positioning such that followup/counter grapples either ALWAYS or NEVER work.
I never seem to have a problem under non-laggy circumstances, except with the Mortar grapple. If my ping is 30+ over my opponent, I know counter-grappling is hopeless. Are you saying make it more lag-friendly? It seems to work fine otherwise.
Latency is probably one of the biggest factors. When mine is over 100, it seems more grapples fail then when it's under 75 (average is 60-85).
The best part is grappling someone near the edge of the map, and ending your grapple at a different angle and distance, falling off the map afterwards. Maybe you'll be lucky enough of certain maps to fall through the ground because of inconsistencies with edges of visible ground and what parts of it actually have clipping.