Today, I experimented. It kind of blew up.
The major lesson of the game was that this is REALLY a finesse army. AV12 skimmers don't stand up to a lot of abuse, as expected. The other issue? Dire Avengers. They're decently shooty for troops, but again they just don't crank out enough damage to be anything other than cleanup crews.
I'm kicking around the Exarch for them. 12 points for the Exarch upgrade, 15 points for BLadestorm, and 5pts extra for Twin Shuriken Catapults. That's a healthy 32 points extra for the guy.
Now, if I dropped the mech autarch, I could probably go to three squads of 7 Avengers w/ Exarchs with twin Shuriken Catapults.
So, each one is good for:
4 shots at BS5
14 shots at BS4.
Or, 12.33 S4 AP5 hits.
Against the average T4 enemy, it's 6.16 wounds, and 2-3 dead after saves on average. With Bladestorm, I go to:
5 shots at BS5
21 shots at BS4
18.1 S4 AP5 hits.
Or, 9.05 wounds. This is 3-5 dead on average, depending on 3+ or 4+ saves. Obviously if I catch someone in the open and deny them saves, I do a little happy dance (which I assure you is quite terrifying).
So, a Bladestorm is a one-turn jump in efficiency that nets me 2-3 more bodies on average. Not bad, but it'll merit some testing.
I'm really not sure how much I'll miss the +1 to reserve rolls, since if I have terrain I should be able to keep my guys safe if I don't get first turn.
The downside? I WILL lose shots on my next turn, though so far I've not really effectively managed to use my Dire Avengers and keep them alive. Slamming 2-3 squads' worth of fire into a single target might help, though they just crumble in assault.
Theoretically I could put Defend on them, but most CC guys have so many attacks already (and I have a puny T3, 4+ statline defensively) that I'm going to lose.
So, for sake of argumentation on the Dire Avengers, let's say I spend some of the points from the Autarch on going up to ten Avengers per squad.
20 shots at BS4
2-3.75 dead guys after saves.
More shots vs. a similarly-costly squad of 8 w/ Exarch, though Bladestorm really nets me another 2 wounds.
131 for 8 Avengers w/ Exarch w/ Twin Cats and Bladestorm, or 120 for 10 Avengers. The comparison favors the 10 Avengers if you get a second turn of shooting, which leads me to think that if I learn to play the army better, I can get more out of my Avengers and not really NEED the Exarch.
Even so, I 'm still going to build some, since I'm going to get another box of Avengers. Got 10 old-school metal ones, got 10 from Xardian (with GS boob-jobs) and 5 from that wave serpent box. So, I can get some options at least...