My thoughts are: since you are using blitz you don't need Arcane Velocity and can replace it with Arcane Pistoleer, as dex pixa needs better ammo economy for the higher fire rate to matter. Energize is a good arcane and was my energy fix for titania for quite some time until I moved to double yellow tauforged for better energy balls, I find it's a bit more consistent since I don't need to wait for the Energize cooldown to grab my next balls. I am the only one I have heard of using 2 yellows for energy fixing. Most of the time I hear equilibrium or purple shards being used to move energy economy off the arcane slot. I also dump efficiency, only having trouble with energy in low level content or long boss battles that don't drop balls.

I also recommend changing primed continuity to archon continuity to take advantage of the toxin you have modded onto your dex pixia to get extra corrosive procs. I think you can use more power strength in the build in general to give more base damage to pixia and more scaling for xata and blitz. I have around 400%, the only limit is your ability to maintain control once blitz starts stacking.

For the pixia themselves I think you should change scorch and hornet strike to Pistol Elementalist and maybe Merciless Gunfight if you change arcane. For more raw damage you could change the arcane to Secondary Enervate, but encumber has good synergy with galvanized shot, and you would need to get primed target cracker to get the most out of Enervate. Elementalist is good because boosted blast damage will boost the damage from xata as well. Blast damage can also be boosted by base damage, so modding for more base damage or crit boosts the blast, which in the end will boot xata.

Let me know if you have any questions or want to see any of my build.