Annihilate the 'crons!

So, we finally threw down the 2 'cron vs 2 Tau game. Apocalypse, no FOC, 2500 per player(5k per team). I was running late, so they rolled mission and such with out me. Annihilate! Damn! Each side had 2 assets. We took the marker field(everything marked within 24") and a Icestorm warhead(10" blast vs vehicles, all 'crons hit take a pinning test). They took some tech snag thing, single use, grabbed one of my area denial nodes. Other asset was a unit gets up on 2+, instead of 4+.
Started the game by making a destroyer squad run off the table, its becoming a theme. Took out swarm after swarm with rail rifles, killing 4 3 base swarms and 2 bases of the 5th by the end of turn 2. Almost everything else got back up. At end of turn 2 we had to barely scratched them. Supposed to finish weekend after next, but there is already talk about calling that one.
Likely next time will be objectives, with us holding a fortification on one end, going the long way. Basically a pro Tau setup, with the exception of no phase out for the 'crons. Not sure I like it, but whatever.
Biggest thing I need to do is look long and hard at that third mission. It has filled me with a undue sense of dread, and I need to face it down. I think I need to just set up my gun line and go all out for the kill. Kill a unit, move to the next. When placing on the long edge, instead of spreading across table to maximise fire lanes, and cutting off support from different elements, I should place everything in a cluster along the flank, forcing the enemy into my fire lanes. I think setting up second may not be disadvantageous. Then I can pick the weak flank and force them to move their strength to me, moving as far as possible.
For this next game, knowing my opponent and knowing my terrain setup before hand, I think I will place all my guns on the wall, plugging the hole in the center and the ends with my nodes. Likely place my HHs behind the wall, so they can move forward over the wall, landing in front, to unleash death first turn. Top of the walls will be loaded with markers, snipers, and broadside. Mind you, I will have to set up with a partner and space is limited, but it should work out, table is 5' wide. Pathfinder Devilfishes will find a place behind the nodes giving LoS for deep strike across the board. If the monoliths land in the back field, I hope to use my teammates FWs with EMPs to take them out.