I am at 65% of the game and almost all my tech-priests are equipped with Phospor Serpenta and Arc Rifle. I like Plasma weapons, but they are rather CP-hungry. At the same time, Phospor Blaster and Gamma Pistol require no CP but are rather useless.

What's your favorite ranged weapon? I would really like to know if there are viable alternatives to my ranged weapons equipment.

Well there are much better weapons out there - ones that can go through walls and take out half the map (especially if you put them on an upgraded Dominus); however their CP usage is slightly more than the Phosphor Serpenta (2 CP is nothing, I definitely wouldn't call it "CP-hungry" - 5 CP is top tier).

The only negative thing is - especially with an upgraded Dominus - that their AOE is so massive you need to be a tad careful you don't wipe out your own guys (but then again, troops are expendable).

There are also flame-throwers available, which are decent strength with decent AOE, cause burn for a few turns afterwards, and are one of the few ranged weapons doing physical damage.

You're going to want to ensure you grab as much CP as you can, whenever you can - having at least one priest go down the Lex line is pretty much a must, along with equipping lots of CP-grabbing items.