Tips and tricks at 1000 pts?

I'll be playing on Sunday with this list , mostly in 2V2 games.

Can you give me some tips to make the best use of these guys? I can make some slight changes (proxy Ursula with a castellan, add or remove x unit), but I won't be changing much in 2 days

Also don't mind the incorrect point numbers, it's from new recruit, but this list still works at 1000pts.

Cheers!

Cadian Castellan (60pts): Close Combat Weapon, Warlord, Chainsword, Grand Strategist, Laspistol 5x Cadian Command Squad (85pts) 4x Platoon Command Squad (60pts)

10x Cadian Shock Troops (60pts) 10x Cadian Shock Troops (60pts) 10x Cadian Shock Troops (60pts) 10x Cadian Shock Troops (60pts)

3x Heavy Weapons Squad (50pts) Rogal Dorn Battle Tank (240pts): Armoured tracks, Heavy Stubber, Castigator Gatling Cannon, Twin Battle Cannons 3x Scout Sentinels (165pts) Chimera (70pts): Armoured Tracks, Lasgun Array, Chimera Multi-laser, Heavy Bolter