So I'm guessing the points were 1500ish, breakdown as follows.
2x Ethereal - 90
Cadre fireblade - 42
6x 5man strike teams - 240
Firesight marksman - 24
A broadside with rail rifle and SMS+drones (missile?) - 223
Sensor tower - 33
Shadowsun - 167
3 stealth suits w/ beacon and 2x shield drones - 126
6x XV8s with six fusion blasters, five flamers, one sad reject with only burst cannons, and one Tough Cookie with shield generator and stimulant injector and 12 shield drones - 562
Don't take this the wrong way but you should read through some of the other army building threads if you want to beat your opponents. Taking so many points inefficient things with our index will not serve you well. I'll try to point out some improvements.
Shadowsun is menh for her points. Spend LESS points and get a tougher chassis with more wounds and double the shots from a quad fusion commander. Easy fix there.
You have 2 Ethereals giving FNP to save a handful of units. I'd say stick with one, if any, and put it near stuff that matters. Most of the time you're saving things that don't really matter and spending a LOT of points on it. Not to mention you have MSU firewarriors so you certainly don't need the ethereal giving out leadership buffs since it likely won't matter.
Fireblade is fine with strike teams but not taking ANY gun drones is really a mistake. He should definitely only be taken if gun drones are present in my opinion. Save more points there.
Firesight is fine if only to be a hidden markerlight to get our new stratagem going or to pile on the extra hits if needed. Prior to the release of CA I would have said axe him but now I'm not as sure.
Poor poor broadside. Seems ok but really just doesn't put out enough punch to make it worthwhile for 223 points. Much, MUCH rather have a CIB commander with a pair of drones for 154.
Sensor tower is an even worse version of the tetra and tetras are pretty bad for putting out markerlights. Switch to hidden lights in the strike teams or go all in with loads of pathfinders. Sadly, markerdrones just don't cut it like they used to.
Stealthsuits are good, keep them but don't deploy them until VERY late or last. Make sure they are within about 20" of the QFC or flamer suit intended target. 8" move, d6" advance, 1" drop the beacon, 8 or 9" threat range on the guns. Definitely don't need to be hyper aggressive with your deploy on these.
Lastly, you've spent over a third of your points on split damage type and range weapons just so you could gimmick a short range deepstrike AND it bit you because of a bad deploy. If you've spent THAT many points on a "deathstar" and you need things to go right, make sure you are redundant and take multiple stealth suit squads with beacons. I do not condone doing this but it's your game, you play it how you want. HIGHLY recommend not taking that many crisis in a blob especially with different weapons. Take 3 as all flamers and drop them in but also take 3 and go full missile pods or full CIB (my recommendation) and have two separate deadly squads.
I recommend also taking pathfinders. With hidden weapons and the fact that we don't need a ton of lights to hit 5 anymore, I think they do a great job.
Ideally your final list will have 10-15% of points in buffing units and definitely no more than that.
You need some alpha strike or ability to get to big units and make them fall over. QFC or multiple QFC's will definitely put the fear of god into your opponent.
CIB's are one of the best guns in our index, I suggest finding ways to utilize them. Overcharge on anything that's not t3 or t5 and anything that has multiple wounds. Rinse repeat until it falls over.
Gun drones. Lots of gun drones. Shield drones in the mix are great too to keep people from targeting the drones without any real chance of saving. Going strictly shield drones leaves a little on the table along with your buffing units that have zero bite. I personally don't like this method but if you have enough commanders, this may actually be a very strong strategy since they will more than make up for not having gun drones firing.
Sorry, long winded post but you are using some weaker stuff and expecting anything will beat your opponent when simply it just isn't the case. Codex > index.