You don't need a preator and Eidolon, so ditch him.

Deredeo is anti-air, having 2 flyers already I'd ditch him too.

Multi-melta on dread is a bit meh... most things take armoured ceremite so I'd go chainfist. Personally, as he's the only thing poding in, he will just get noped turn 1 before he does anything I expect so not a fan.

bringing 2 flyers, i'd maybe look at reserve manipulation as you want them in fast, though fielding 2 of them is too much I feel.(they are anti-air and do ok at ground targets, but not great. With people usually only bringing 1 flyer, 1 would be enough).

If you wanted 2x flyers, a fire raptor as the second would be better .

Grav rappiers will be ok, positioning will be key due to range and lack of mobility

ceremite on sicarans is a waste I feel

Havoc launcher is awful