Thats a pretty good army!
I would give you extra kudos for playing a Necron army without the rez orb. I have never seen one at a tourney.
If you wanted to make it harder, add the rez orb and get a monolith, the monolith is unreal, however its best value may lie in teleporting necrons around and allowing for the reroll of their WBB roll, realize a unit that ports get to roll it twice, meaning 75% of knockouts for one unit, become meaningless in general.
That ability combined with the rez orb is so powerufl that many may criticize your list for not taking them. I actually like your structure, I think it is mobile, atractive, plausible and even a little thematic. Good luck whatever you chose!