I need to agree with Lance - but there is a bit more to it. AI raids won't try to run out of your planet before they destroy something important - yours need to when raiding. And your change for next version that makes everything hit the ship when it jumps means that raid starships (and transports to less extent) will have _very_ high chance to insta-die at WH.
Imagine for example dozen of artillery guardian or fort salvos coming their way - normally they would never catch up - now they will make sure that raid starship and transports will lose tons of health.
From other point - removing missile immunity from raid will make it's counter to work on them - missile tower will few-shot them - as well as for example missile guard posts.
Can you hit vampire claws as well while you are at it... ? They are quite uber due to having no counters (at least when used by AI in large amounts) but not sure how will they fare without that missile immunity.