I do not like your blasters on gunboats. In case you'll need to shoot a tank, you'll be wasting all the poison shots, if shooting at infantry, 1 S8 shot won't change your day... With that 45pts you could bring the kab up to 10 per unit. And splinter cannons, with 10 kab in rapid fire distance you'll have 20 TL shots, would those 4 more make a big difference to pay for?
Also, imo too many night shields...you are spending 120pts for them, you could take a whole unit of scourges instead. Your choice, but mainly on planes they are useless to me. If you jinx you lose the entire next turn, possibly going back to reserve.
At last, what are your plans for wracks? They are worse than grots in assault, they are worse that blasterborn in shooting, and they cost the same. You have an haemy, so I could guess he will join them. With this codex I think the only viable use for them is the scalpel formation with 2 units on venom.