CCS is fine but drop the power weapon as yuor squad is based for shooting and if you do get into combat you'll probably go last and end up dying before using that power weapon.
Do you need demos? I don't think so really. The demo charge is only one shot and you have meltas already. Sure you can melta bomb a tank but surely you'd want to stop inside your transport as long as possible as guard outside of chimeras die, rapidly. Oh, you need more troops as 20 guard won't last long.
Hounds are ok. Sentinels are costly and weak, if you want them take autocannons and get side or rear armour on vehicles but you can still threaten infantry too.
Executioner is fine but ditch the lascannon and heavy bolters on the battle tanks. Your large blast is ok for light armour and infantry, but the lascannon is good for anti tank and will hit 50/50. I'd keep the tanks cheap and invest points else where, dropping those points gains you about 70 points back.
Hope that helps!