Necron 2500 point list

OK so here is my first attempt at making a 2500 point list for the Necrons. I went for negating enemy forces while making me almost impossible to remove from an objective. I also attempted to cause damage to my opponent in their phase as well as mine. please let me know what you think.

HQ
Imotekh the storm lord
Royal court - 1 cryptek Harbinger of transmogrification with seismic Crucible
1 lord with res. orb and WarScythe

Elite
C'tan shard with Sentient Singularity, and Writhing Worldscape
deathmarks X10

Troops
20 Necron warriors with a Night Scythe (night Scythe will be used for tomb blades)
10 necron warriors plus a Ghost Ark
10 necron warriors plus a Ghost Ark
10 necron warriors plus a Ghost Ark

Fast Attack
10 Canoptek Scarabs
10 Canoptek Scarabs
5 Tomb Blades with Shield Vanes

Heavy Support
1 Doom Scythe

I think this will be a very competitive list, but please critique it for me. If you have suggestions please don't be afraid to post them.