It's nice to see a list with the psykers in
My criticisms would be... meltabombs in the
CCS - you have a very shooty squad that doesn't look like it intends to move, so I'd take them out since you probably won't use them OR make a barbeque squad/melta squad (flamers and heavy flamer/meltagun spam).
I would also put the Platoon command squad in a chimera instead (find a way to keep the valkyrie in the points though, they're great

Maybe swap with a battle choir?) because then you can benefit from orders

. Are the Medusas squadroned or seperate heavy choices?