I think the event was well done all in all, especially the dramatic setup and the visuals.
There was a lot of moaning on the gallic side because "omg we can't win", but one side is bound to experience that at some point of most battles, and it's one of the reasons why event outcomes shouldn't change the future of the mod (and thereby the future of some factions and their players accomplishments).
About the lag, because 2 x 10x10 collision checks (probably?) take less bandwidth than 20x20 collision checks (I'm guessing it works like that in the FL engine?) the event can be split into 2 battles in 2 systems where player numbers are controlled by the staff activating and de-activating jump holes near the spawn points. And/or make an additional dedicated event server with the right restarts like for the destruction of Toledo event.