Interesting list. I especially like the inclusion of Darkstrider (and getting Ob Sec on the two Kroot squads might be handy, even though I generally refuse to take more than one squad of Kroot).
Okay, some thoughts:
About the Breachers, I forget--do you have to pay for the Guardian Drone, or do they just get it? If you have to pay, I'd ditch it. A Daemon Save ain't worth it (sayeth the Daemon player). Park the pair of gun drones in their path and you get the same basic effect for zero cost. I *still* think you won't get their super-shots very often, given the ranges needed, but I'm interested to hear how they play out for you.
In terms of getting the points for an Ethereal, here is my advice on what to cut:
All Target Locks: I have a feeling we're just going to disagree on this issue, but I've found the Target Lock to be the most consistently useless thing in a Crisis Suit's arsenal. The number of times splitting Crisis Team firepower has paid off is vastly outweighed by the number of times it has boned me good. I realize overkill is a concern, but it really only becomes a concern in the late game, when units of not-quite-dead guys are straggling around. Gun Drones, though, are for stragglers. Not whole XV8s. The only time I see it as worth it is in giant Farsight-Bomb style lists which need them because they contain sufficient firepower to actually destroy multiple units themselves. Your little two-suit units don't qualify.
DPod on the Hammerhead: Anytime you jink with a Hammerhead, you have wasted a Hammerhead (*especially* with an Ion Cannon). It has solid front armor and cover isn't that hard to come by. It will be fine without it.
Fusion Guns on Stealths: I will say that a notable weakness in your army is the capacity to deal with Land Raiders, but two Fusion Guns does not solve this problem, anyway, so you may as well save the points. Plus there's the whole "but now my burst cannons are shooting at Land Raiders" problem, which I think is a bigger problem overall than "I can't kill that Land Raider I might, one day, encounter."
Counterfire Defense on the Ghostkeel: The Ghostkeel is going to live 6" away from the Stealths, anyway, so there is *plenty* of boosted overwatch coming your way.
Bam. Ethereal is yours.
Now, about AV14 vehicles...
Obviously, with the Wall of Mirrors, anything with a low rear armor is toast. I don't think fusion blasters in Stealth Squads is necessarily the answer to Land Raiders/Monoliths/etc.. That said, if you are worried about this kind of thing (does your metagame feature a lot of Raiders?), you could save the points for the Ethereal by switching back to the Fusion Collider on the Ghostkeel and taking Fusion Blasters (which I think still saves you the points needed). Then you've got enough melta (4 shots, more or less) to threaten those big, heavy tanks.
Anyway, those are my .02. Good luck with the list!