+1 for the shattershard!
Big recommendation from me is either drop a wrack from the bigger group to fit in a haemy (the LG is replaced by the one the haemy carries) or deploy them out of the Raider together to ensure the big wrack group starts with 2 pain tokens. The Furious Charge boost is more than worth it in my experience. With FC, I'd pit 10 wracks against a space marine squad any day of the week, never mind guardsmen.
The other thing I've learned is if you have the opportunity to hang back and shoot with the lances before charging (only if you can do it without having your boats blown up, mind you), that turn of AT shooting can sometimes make a huge difference.
I guess my only question is where are the haemys going? 2 each with the grots?
The list itself looks like fun, and I'm sorely tempted to try a variation. I like the power axes, though I've only used venom blades. I second the vote to hear about the game!
I dedicate these deaths to Odin Allfather, Spearshaker, One Eye.
Fleet Shadowmaker - Kabal of the Dying Sun; Cult of Marrow Excised; Coven of Lambent Hunger
Sons of the Last Breath - Chaos Space Marines
Host of Shattered Purity - Chaos Daemons