Next up for elites is the Wyrdvane Psykers, the renamed and changed psyker battle squad. Oh boy these guys went from really good the kinda meh. Not bad mind you, just a definite shadow of what they were before. While it was no surprise that they lost unique powers and gained BRB ones, their straight utility from the old powers to the new are somewhat less. But you can do more with them now and be flexible.
What changed is that they are now brotherhood of psykers(good), lost the overseer(good), and gained rule book psychic powers(not as good). The points are a little more, with the same base price but with 12pts for each additional one up to 10 total. They are ML1 and can generate powers from biomancy, divination, pyromancy, and telekinesis. Some of these are more useful than others but overall they have the ability to change tactics depedning on the opponent you are facing. They can use daemonology as well and are your best choice if you want to go that route. Due to brotherhood of psykers, they can fail a few perils before they go down, giving you more play time with them.
Unlike before there is no bonus for taking more, and I really don't see a reason to take more than the base squad. They are pretty squishy no matter how many you have, with only a chimera or taurox upping their survivability but limiting their powers they can use. The base squad will do you fine and is still pretty cheap.
As to what to take, telekinesis and divination are your better choices here. Not necessarily for prescience, more for the other useful powers that the table has. As a unit they are not the great for adding warp charges, as astropaths will give you the same number and are a lot cheaper if you are looking for extra warp charges. You can use them as a back field unit to throw out a few buffing powers a game, but honestly a ML2 primaris will give you a lot more utility.
Because of their squishyness, I see them in transports being the better option, which means you want to focus on witchfires. This means telekinesis or pyromancy. Between the two, telekinesis is better simply because it has a better primaris power, with only one roll on the table you want to hedge your bets on something useful. The primaris power has strikedown as well, causing enemy units to move through difficult terrian in the open, which is very useful, especially against units like gaunt squads, orks, jump pack units, really any infantry that wants to move faster towards you. Plus if you get lucky and get the large barrage S 10 AP1 power, then you can get some serious damage.
Pyromancy is ok, the problem being its primaris is basically a heavy flamer. So your going to need to get close, meaning even in a vehicle their is a high chance of it getting knocked out before they get anywhere. Overall its just too unreliable to count on. The same goes for biomancy. It has a lot of good powers, but also a lot that only affect the unit, and they just are not good enough to be worth that. You can make the S 5 or one of the other boons, but in they end they are still pretty squishy and have to get close to be useful. They really don't belong anywhere in CC.
Daemonology is interesting. They are your best choice if you want to use these powers, and their best role is using sanctic powers if you are facing off against daemons. If you really want to summon some daemons on your side, you sure can do it. Not saying its a reliable or effective tactic, but its an option.
There real problem is that there is no real clear role to fit them into. They can kinda be ok at buffing, but really don't generate enough warp charges to go that route effectively these days. They are too squishy for all the biomancy buffs to really risk taking that table. Telekinesis is a pretty useful table and gives you access to a few good witchfires as well as buffing powers. Its the most reliable table for these guys. Divination is good as well, but they just don't generate enough warp charges to be really good at prescience. Keeping them as a backup prescience is not a bad option, but not really a great one either.
The two best ways I can see to play them, is either as a mobile witch fire unit or as a divination back up, helping spread your coverage and using the total warp charges to get prescience on the needed units.
Overall they are not outright bad, they just are no where near as useful as they once were.
GG