I recently bought the 7th ed rules so the Psychic phase and all its rules are the predominant aspect I am trying to catch up on.
Also the GK FAQ came out recently too. Resulting in a better understanding of our friend Thawn!
He can't have the Divination discipline as I originally thought but rather the Daemonology (Sanctic) discipline. So he can have two powers in that discipline only, but at least it is a good one.
The Primaris is Meh, but Hammerhand has improved, Gate of Infinity has serious uses (skulls and mystics will make a comeback), Sanctuary is very different but great for termies, Purge Soul has some definite uses, Cleansing flame! is quite good!, and Vortex of Doom is ... well DOOM!
So to summarize for the 75 points Thawn adds ...
- Psychic Mastery Level 2 - booyah!
- access to some very good psy power
s (Sanctic)
- Force weapon power, Sanctic Primaris (again meh) and TWO of the other 6 good to very good Sanctic ones!
- Fearless - never bad
- WS 5 w init 6 halberd!
- 'I shall not yield' went from pesky to good ...
- in tournaments with the new FOC he can become the warlord and deny 'Slay the Warlord' points!
- A troop choice, a very difficult to remove Objective Securing choice

- When he is separated from his unit after death, he comes back as another source of Warp Charge points
I would occasionally take him in 6th with some good results but questioned cost, still expensive but I am less likely to question cost!
GM Rex