Not that I'll be able to make it, but after playing the last 14v14 I think it is vitally important, especially in a TC match, to have the lances be mixed role.
High command issues orders down only to other lance leaders, and lance leaders up to high command. If Lance 3 is a brawlers only group and needs fire support, he has to relay this request up to the command channel and then await high command to order Lance 2, the support lance, to peel one or two guys off to help. Now Lance 2 is spread out across multiple combat fronts and communication and coordination starts to fray.
On the flip side, if you have mixed lances, and Lance 3 runs into a situation where it needs fire support, it need only look to its own Owens Prime or Hollander rather than have to request an asset to be sent over from a different lance by high command.
Also, mixed lances are boss fluff-tacular and I heartily approve.