I would recommend Ion weapons to better aim deathrain. So either Omicron Lambda w/ ion cannon or Scimitar Bomber w/ extra munitions and 2 ion pulse missiles or Tempest Advanced w/ X1, accuracy corrector & ion pulse missile.
What else can I do with 24 points?
If you are using a lot of ordnance, may I suggest
Lorrir in a Mk.II to help shed stress a little easier. Or if you're feeling cheeky Fel's Wrath in a Mk.II.
There's also Captain Yorr to help with stress management and might be super effective if you run into stress builds. Or take a Jade Cow (OGP + Mara) and have a primary stress-er in your squad.
24pts is a Bread number. The amount of actual possibilities is near limitless. It's all about finding that Butter limit to make it delicious.
Simple..........doom shuttle