[DaisyDuke]

Two suggestions
1) lose an obliterater and pow fist to gain the mayhem pack data slate. If you did this I'd be tempted to put Lord in terminater arm and put him with the remaining obliteraters
2) hell brutes are 100 base not 105.

The mayhem pack can turn the tide to your favour, it's amazing what three dreads can do

 

[DaisyDuke]

Yes

 

[DaisyDuke]

You roll their reserves roll as if they are a unit but they deep strike as individuals.
How about a combi for the 9 man unit and bombs on the lord then dirge casters for the rhino or havoc on the plasma box,
Personally I have had great success with havoc launchers